Classifications

• • 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
  • H01B7/29—Protection against damage caused by extremes of temperature or by flame
  • H01B7/295—Protection against damage caused by extremes of temperature or by flame using material resistant to flame
• • 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
  • H01B3/302—Polyurethanes or polythiourethanes; Polyurea or polythiourea

Definitions

• the invention relates to electrical insulating parts according to the preamble of claim 1 and in particular sheaths for electrical conductors and cables.
• polyesters with good electrical insulation properties are particularly suitable.
• the insulating material can be pulled as a hose over an electrical cable or sprayed directly onto the part to be insulated. It is also possible to wind the insulating material around the electrical conductor in the form of a film. The film is wound in several layers on top of one another in order to achieve the best possible electrical insulation. If a polyester film is used, the individual layers cannot be welded and cannot be connected to one another. A coating with additives that have high cohesive forces is therefore necessary in order to be able to mechanically connect the individual wound film layers to one another.
• this film is provided with stabilizers or anti-aging agents. It is also known to add color additives to the polyester film.
• the polyester film Since the polyester film is highly flammable and flammable, it is equipped with flame retardant or flame retardant agents.
• Technically important flame retardants included at least one of the following: Phosphorus, antimony, chlorine, bromine or nitrogen.
• Known flame retardants for plastics are chlorinated paraffins, highly chlorinated bicyclic compounds and bromine compounds.
• the organic halogen compounds are always used together with antimony trioxide.
• Inorganic phosphorus compounds, organic phosphonic acids or halogenated phosphorus compounds are also frequently found in flame retardants for plastics.
• the invention has for its object to make available electrical insulating parts which are provided with a flame-retardant coating.
• the flame-retardant coating is not intended to impair the Properties of the insulating material.
• Another object of the invention is to use connections for a flame-resistant coating, that do not lead to toxic or corrosive products in the event of fire.
• the electrical insulating parts which are produced from the polyester film and the halogen-free crosslinkable coating according to the invention are distinguished by improved mechanical properties, greatly reduced smoke density and by a better adhesive bond between the individual wound polyester layers. Comprehensive safety is achieved when this coating is applied to the polyester, since the toxicity and corrosiveness of the flue gases are significantly reduced in the event of a fire.
• the electrical insulating parts according to the invention are made of polyester, preferably in the form of a film, and a flame-retardant coating which contains a crosslinked halogen-free mixture of unsaturated polyester resin, crosslinking agents or chain extenders, catalysts, stabilizers or antiaging agents, dyes and flame retardants.
• the electrical parts insulated with the polyester film and the halogen-free coating are characterized by high abrasion resistance, notch resistance, dielectric strength, tensile strength and temperature resistance up to approximately 150 ° C.
• the additives of the coating do not have to be added in a significantly increased concentration in order to lead to sufficient flame retardancy.
• the above-described disadvantages of reduced flame retardancy or reduced strength are eliminated by using different combinations of flame retardants from two different connecting groups.
• the first linking group contains inorganic phosphate esters, phosphonated polyols, red phosphorus and organic phosphates.
• organic phosphates alkyl phosphates, allyl phosphates, aryl phosphates and in particular trioctyl phosphate, cresyl phosphate, phenyl phosphate, cresyl phenyl phosphate and ethyl acetyl hydroxybenzyl phosphate are preferably used. Connections from this first group are combined with connections from a second group.
• This second group of compounds contains boric acid, ammonium sulfonamides, inorganic phosphates, polyphosphates, borates and metal hydroxides.
• Particularly suitable borates are barium metaborates, zinc borates and ammonium borates; metal hydroxides which are preferably used are aluminum and magnesium hydroxides.
• Suitable inorganic phosphates include boron phosphates, and polyphosphates include ammonium polyphosphates.
• the improved flame retardancy is based on a synergistic effect of the flame protection system produced from the two groups mentioned. It is therefore not necessary to increase the dosage of the flame retardants.
• the amount of flame retardants from the first group is in the range from 0 to 80% by weight, the amount of flame retardants from the second group in the range from 0 to 70% by weight. Even small amounts of flame retardants from these two groups are sufficient to achieve high flame retardancy. Preferably 10-40% by weight of flame retardants from the first group and 20-60% by weight of flame retardants from the second group are used.
• the unsaturated polyester resin is made from terephthalic acid, aminocarboxylic acid or ⁇ -aminolauric acid.
• Preferred aryl or alkyl diisocyanates are toluyl isocyanate, 4,4'-methylene di (phenyl isocyanate), naphthalene-1, 5 or naphthalene, 1,4-diisocyanate, methylene tri (phenyl isocyanate) or hexamethylene diisocyanate.
• One or more of the compounds from the group of amines, hydrides, metal oxides, caroxylates, organometallic compounds or tetramethylbutane diamine, diazobicyclooctane, dibutyltin dilaurate or tin octate can be selected as the catalyst for the crosslinking reaction.
• Compounds of the mononuclear or polynuclear phenols substituted in the ortho or para position, the bisbenzooxazoles, the coumarin derivatives, polycarbodiimides, the aromatic amines, thioethers or the phosphites are preferably selected as stabilizers or anti-aging agents. The addition of these substances avoids the undesirable change in the chemical and physical structure of the insulating part during use.
• colorants on an inorganic or organic basis are used.
• suitable inorganic compounds are titanium dioxide, carbon black, iron oxide, chromium oxide, mixed oxides or spinel compounds
• suitable organic-based dyes are the azo dyes, phthalocyanines or dioxazines.
• lubricants are added to the coating.
• Suitable compounds are olefinic ketones or compounds based on wax, soap or oil.

Landscapes

• Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Organic Insulating Materials (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Laminated Bodies (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6330713

Family Applications (1)

Country Status (2)

Citations (7)

Family Cites Families (4)

• 1987
  • 1987-07-01 DE DE19873721792 patent/DE3721792A1/de active Granted
• 1988
  • 1988-04-26 EP EP88106680A patent/EP0297241A3/fr not_active Withdrawn

Patent Citations (7)

Non-Patent Citations (2)

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