Flame resistant insulated electrical wire and cable construction

• US 4,430,384 A
• Filed: 01/19/1981
• Issued: 02/07/1984
• Est. Priority Date: 09/07/1979
• Status: Expired due to Fees

• Current Assignee: Label-Aire, Inc. (Cenveo Incorporated)
• Original Assignee: Subtex, Inc.
• Inventors: George, Stephen
• Primary Examiner(s): KENDELL, LORRAINE
• Application Number:
  US06/225,889
• Time in Patent Office: 1,114 Days
• Field of Search: 174/121 SR, 174/121 A, 174/121 R, 428/253, 428/285, 428/286, 428/343, 428/355, 428/377, 428/383, 428/389, 428/384, 428/432, 428/251
• US Class Current: 428/377
• CPC Class Codes: C04B 26/06 Acrylates
• CPC Class Codes: C04B 28/24 containing alkyl, ammonium or metal silicates; containing silica sols reaction mixtures resulting in mineral polymers C04B28/006; polymeric reaction products of alkali metal silicates with isocyanates C08G18/3895
• CPC Class Codes: H01B 3/02 mainly consisting of inorganic substances
• CPC Class Codes: H01B 7/29 Protection against damage caused by extremes of temperature or by flame heat dissipation or conduction H01B7/42
• CPC Class Codes: Y10T 428/28 Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2936 Wound or wrapped core or coating [i.e., spiral or helical]
• CPC Class Codes: Y10T 428/2947 Synthetic resin or polymer in plural coatings, each of different type
• CPC Class Codes: Y10T 428/2949 Glass, ceramic or metal oxide in coating
• CPC Class Codes: Y10T 428/2958 Metal or metal compound in coating
• CPC Class Codes: Y10T 442/2631 Coating or impregnation provides heat or fire protection
• CPC Class Codes: Y10T 442/2992 Coated or impregnated glass fiber fabric
• CPC Class Codes: Y10T 442/3976 Including strand which is stated to have specific attributes [e.g., heat or fire resistance, chemical or solvent resistance, high absorption for aqueous composition, water solubility, heat shrinkability, etc.]
• CPC Class Codes: Y10T 442/40 Knit fabric [i.e., knit strand or strip material]
• CPC Class Codes: Y10T 442/696 Including strand or fiber material which is stated to have specific attributes [e.g., heat or fire resistance, chemical or solvent resistance, high absorption for aqueous compositions, water solubility, heat shrinkability, etc.]

Abstract

A flame resistant insulated electrical wire and/or cable construction formed by wrapping a wire or cable conductor with a heat resistant flexible refractory tape comprising a porous base fabric, preferably a knit fiberglass fabric that has been coated and impregnated with refractory materials. These refractory materials are bonded to both the surface and interstices of the base fabric by means of a bonding agent, such that the fabric remains flexible and retains its stretch properties. In the presence of relatively extreme temperature and heat (e.g., above 1750° F.), the bonding agent will decompose without flaming, while the refractory materials will fuse into the softened surface of the knit fiberglass base fabric forming a high temperature resistant structure with ceramic qualities and insulative properties.

Claims

1. A high temperature and flame resistant insulated wire or cable construction comprising:

an electrical conductor;

an insulating tape wrapped around said conductor, said insulating tape comprising;

a porous flame resistant base fabric;

a refractory coating comprising refractory materials and a bonding agent, said refractory coating formed on the surface and interstices of said base fabric by applying said refractory coating to both sides of said fabric, and said refractory materials being capable of fusing with said porous base fabric at elevated temperatures;

a polymeric coating formed on the outside surface of one of the refractory coatings; and

an adhesive applied to the outside surface of the other of said refractory coatings.

2. An insulated wire or cable construction as in claim 1 in which the refractory materials are alumina, zirconia, calcium silicate, sisicon dioxide or mixtures thereof.

3. An insulated wire or cable construction as in claim 1 in which the bonding agent is acrylic latex resin or acrylic latex resin and colloidal silica.

4. An insulated wire or cable construction as in claim 3 in which the bonding agent also comprises a thickening agent.

5. An insulated wire or cable construction as in claim 1 in which the porous flame resistant base fabric is a knitted fiberglass, a woven fiberglass or a non-woven, porous web of fiberglass.

6. An insulated wire or cable construction as in claim 1 wherein the polymeric coating comprises polyvinyl chloride.