FLAME RETARDANT ROLLING DOOR

Abstract: A flame-retardant, coated fabric material, for use in the manufacture of rolling-door panels, door blades, or leaves, comprises a flame-retardant base fabric 5 that is woven from a monofilament yarn 2,3 that is extruded from a mixture comprising a thermoplastic material and a flame-retardant additive. A flame-retardant coating agent is applied to the surface of the base fabric 5 to form a coating 4. It is particularly designed for use in the kind of high-speed, light-weight doors currently found in the garages and vehicle bays of warehouses, factories, and other industrial facilities. In addition to being much lighter than the metal doors being replaced, the material has to its further advantage a flame-retardancy not present in earlier fabric doors.

Description: This invention relates to the use of fabric materials in the manufacture of rolling doors and door blades or leaves. More specifically the invention teaches the use of fireproof yarns and coatings in the production of rolling door panels, door blades or leaves. This invention generally relates to the production of light-weight garage-type doors used in warehouses, industrial facilities, and the like. With the goal of reducing costs associated with heating such large buildings and rooms, interest in doors that could be opened and closed in a minimal time developed. Fabric composites appeared as an alternative to metal for the actual door panel. Their light weight allows for quick operation at a lower cost than that associated with a metal door. Doors of this variety have been made in two forms. The first, a rolling door, is conceptually much like a window shade. When opened, the pliable single-piece door leaf is pulled upward into a roll above and parallel to the upper horizontal edge of the door opening. The other form is that of a door composed of a number of non-pliable horizontal blades or sections joined together. Each section can be visualized as basically an elongated rectangle whose longer dimension is approximately equal to the width of the door opening. The door is assembled by joining a suitable number of sections together with the longer dimension horizontal in the finished product, the door operating on a familiar track arrangement, such that when opened, it lies parallel and adjacent to the surface of the ceiling. DE-A-3 706 789 relates to a flexible door leaf that is made from synthetic resin material or rubber and that is particularly suitable for use as a rolling door. The leaf has an inner structure formed of metal wires lying closely adjacent to one another. The use in the leaf of further layers of fire protective matting is mentioned, so as to inhibit fire. The introduction of fabrics poses a new hazard not present with metal doors - that of fire. The success and future potential of these light-weight doors heightens the need for fireproof or flame-retardant fabric materials. That need is satisfied by the invention disclosed and described below. It is known from US-A-4 594 286 to make a flame-retardant fabric from a substrate that is woven from yarns of synthetic fibres and that is intimately coated with a coating containing, inter alia , fire retardant chemicals. The substrate is preferably forced of essentially untwisted, continuous multi-filament yarns such as polyester or nylon. The coated fabric is described as being suitable for use for tenting, tarpaulins and protective clothing. The invention provides a flame-retardant, rolling-door panel or door blade or leaf, comprising: a flame-retardant base fabric woven from a monofilament yarn that has been extruded from a mixture comprising a thermoplastic material and a flame-retardant additive; and a flame-retardant coating formed by application of a flame-retardant coating agent to the surface of the base fabric. The invention further provides the use of a fabric for the manufacture of a flame-retardant, rolling-door panel or door blade or leaf as described above. The flame-retardant rolling-door panels, door blades or leaves of the present invention are produced by applying flame-retardant coatings to base fabrics woven from flame-retardant monofilament yarns. The monofilament yarns used in the weaving operation are preferably extruded from a mixture of polyester and flame-retardant additives. These additives, in addition to their flame-retardant properties, allow the yarn to be extruded at a lower temperature than that normally required for polyester monofilament yarn. Once the fabric is woven, it is given a flame-retardant coating which provides, in addition to a further degree of fireproofing, increased bulk, stiffness, and rigidity to the material. Polyvinylchloride, silicone rubber, and acrylics can be used as coatings. Additional flame-retardant material can be mixed with the coatings for further protection. This invention provides the advantages that neither yarn nor coating support combustion. Both the yarn and the final door structure are non-dripping and self-extinguishing. Finally, as noted above, the polymer blend used to produce the monofilament yarn can be extruded at low temperatures. One embodiment of the present invention will now be described, by way of example only, with reference to Figure 1, which is a cross-sectional view of a coated, woven base fabric used to make the rolling-door panels, blades, or leaves of the present invention. Figure 1 shows a section 1 of a coated, woven base fabric 5 used for the flame-retardant rolling-door panels, blades or leaves of the present invention. In this enlarged cross-sectional view, warp strands 2 interweave with weft strands 3 in a plain weave pattern. It is not to be assumed, however, that the base fabrics 5 required for the practice of this invention must be so woven; other weave patterns can equally be used with the same beneficial result. Also shown in Figure 1 is the coating 4, which gives the base fabric 5 added thickness, stiffness and bulk as well as contributing to its fireproofing and flame-retardant characteristics. With reference first to the monofilament yarns required for the weaving of the base fabric 5, polyester with flame-retardant additives is the preferred composition. The flame-retardant additive may be polymeric bromoglycidylether, mixed with antimony trioxide, or it may be poly-(2,6-dibromophenylene oxide), mixed with antimony trioxide. Two workable compositions can be offered by way of example. One is a mixture having proportions, by weight, of about 75% polyester and about 20% polymeric bromoglycidylether mixed with about 5% antimony trioxide. A second workable composition is a mixture having proportions, by weight, of about 80% polyester, about 16% poly-(2,6-dibromophenylene oxide), and about 4% antimony trioxide. Both of these compositions can be extruded in monofilament strands at low temperature, and have the flame-retardant properties required for the practice of this invention. Generally, in accordance with the present invention, the composition from which the monofilament yarn is extruded can have the proportions, by weight, of about 80% polyester to about 20% flame-retardant additive mixture. The latter mixture includes the recommended, or preferred, additive poly-(2,6-dibromophenylene oxide) which can be obtained from the Great Lakes Chemical Corp. under the trade name PO64P. Antimony trioxide is mixed with PO64P and acts as synergist. The flame-retardant additive mixture is approximately 3 parts PO64P to 1 part antimony trioxide, so that these represent about 15% by weight of flame-retardant additive and about 5% by weight of synergist, respectively, of the composition as a whole. The above percentages should not be taken to be hard and fast figures. The most preferred range for the percentage by weight of the polyester runs from 75% to 80%, and, in any event, it should preferably not exceed 85%. The preferred range for the percentage by weight of PO64P runs from 15% to 25%, ideally, 15% to 20%, and, in any event, should preferably not fall below 15%. The most preferred range for the percentage by weight of antimony trioxide is 4 to 5%, ideally 5%, but preferably should not be below 3%. In place of polyester (PET), any other thermoplastic, such as, for example, polybutylene terephthalate (PBT), polyolefin, or polyamide, can be used, depending on the application and end use, as the primary component of the monofilament yarn with good result. The monofilament yarns for weaving the base fabric are produced by melt-extruding the polyester/flame-retardant blend through a die. The hot filaments are then quenched in a water bath having a temperature between 110°F (43°C) and 170°F (77°C). A take-up roll pulls the filaments through the bath at 40 to 50 feet (12 to 15 m) per minute. The filaments are then double-drawn and single-relaxed through forced hot-air ovens. Optionally, the first draw can be carried out in a hot-water bath. The draw oven temperatures are between 200°F (93°C) and 400°F (204°C), while the relax oven temperatures are between 350°F (177°C) and 450°F (232°C). A 5.3% total degree of drawing and approximately 8% relax back is recommended for obtaining the correct filament properties. We now turn our attention to a discussion of the coatings 4 to be applied to the woven base fabric 5. polyvinylchloride (PVC), silicone rubber, and acrylics all may be employed as coating materials. Polyvinylchloride may be mixed with a flame-retardant coating additive. With particular reference to the use of PVC as a coating agent, the flame-retardant coating additive is preferably included in a concentration of 2% to 3% by weight, a phosphate-type plasticizer, such as, for example, 2-ethyl hexyl di-phenyl phosphate, being recommended. Silicone rubber is used without a flame-retardant coating additive. With further reference to the use of PVC as a coating agent, it is possible to produce this coating in five different colors. Each has the phosphate-type flame-retardant coating additive, 2-ethyl hexyl di-phenyl phosphate, preferably present in 2% to 3% by weight. The colors are obtained by the further addition of the coloring agents in the proportions by weight listed below: When the base fabric is ready to be coated, and the components of the desired coating agent mixed if necessary, a doctor blade is used to apply a first thin coat, which quickly dries. A heavy coat is then applied and heat-set at a temperature of 392°F (200°C). After heat-setting, a curing step is performed at a temperature level in accordance with the table below for the various coating agents that can be used.

Claims: A flame-retardant, rolling-door panel or door blade or leaf, comprising: a flame-retardant base fabric woven from a mono filament yarn that has been extruded from a mixture comprising a thermoplastic material and a flame-retardant additive; and a flame-retardant coating formed by application of a flame-retardant coating agent to the surface of the base fabric. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 1, wherein the thermoplastic material is selected from a group consisting of polyester (PET), polybutylene terephthalate (PBT), polyolefin, and polyamide. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 2, wherein the thermoplastic material of the mixture is polyester. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 3, wherein the mixture consists essentially of about 80% by weight polyester, about 15% by weight flame-retardant additive, and about 5% by weight synergist. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 3, wherein the flame-retardant additive of the mixture is polymeric bromoglycidylether, which is mixed with antimony trioxide, the mixture preferably consisting essentially of about 75% by weight of polyester, about 20% by weight of polymeric bromoglycidylether mixed with about 5% by weight of antimony trioxide. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 3, wherein the flame-retardant additive of the mixture is poly-(2,6-dibromophenylene oxide), which is mixed with antimony trioxide. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 6, wherein the mixture consists essentially of about 80% by weight polyester, about 16% by weight poly-(2,6-dibromophenylene oxide) and about 4% by weight antimony trioxide. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 6, wherein the mixture consists essentially of from 75% to 80% by weight polyester, from 15% to 20% by weight poly-(2,6-dibromophenylene oxide), and 5% by weight antimony trioxide. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 6, wherein the mixture consists essentially of no more than 85% by weight polyester. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 6 or claim 9, wherein the mixture consists essentially of no less than 15% by weight poly-(2,6-dibromophenylene oxide), and no less than 3% antimony trioxide. A flame-retardant, rolling-door panel or door blade or leaf as claimed in any one of the preceding claims, wherein the flame-retardant coating agent is selected from a group consisting of polyvinylchloride (PVC) optionally mixed with a flame-retardant coating additive, silicone rubber, and acrylics. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 11, wherein the flame-retardant coating agent is polyvinylchloride (PVC) mixed with a flame-retardant coating additive. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 12, wherein polyvinylchloride (PVC) is mixed with 2% to 3% by weight of a flame-retardant coating additive. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 12 or claim 13, wherein the flame-retardant coating additive is a phosphate-type plasticizer. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 12 or claim 13, wherein the flame-retardant coating additive is 2-ethyl hexyl diphenyl phosphate. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 15, wherein said flame-retardant coating agent further comprises 5% to 6% by weight of titanium dioxide, so that said flame-retardant coating agent will acquire a white color. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 15, wherein said flame-retardant coating agent further comprises 5% to 6% by weight of silica encapsulated lead chromate/lead molybdate pigment, so that said flame-retardant coating agent will acquire an orange color. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 15, wherein said flame-retardant coating agent further comprises 1% to 1 1/2% by weight of carbon black pigment, so that said flame-retardant coating agent will acquire a black color. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 15, wherein said flame-retardant coating agent further comprises 3% to 4% by weight of brown iron oxide pigment and 2% to 5% by weight of titanium dioxide, so that said flame-retardant coating agent will acquire a brown color. A flame-retardant, rolling-door panel or door blade or leaf as claimed in claim 15, wherein said flame-retardant coating agent further comprises 1% to 2% by weight of phthalocyanine blue pigment and 4% to 5% by weight of titanium dioxide, so that said flame-retardant coating agent will acquire a blue color. The use of a fabric for the manufacture of a flame-retardant, rolling-door panel or door blade or leaf as claimed in any one of the preceding claims.

Inventors: MITCHELL, LARRY L., TONEY, CRAYTON G.
Applicants: ALBANY INTERNATIONAL CORP.
Application year: 1990
Main classification: E06B5
IPC codes: D06M101, D06M11, D01F6, D06M13, D06M15, E06B9, E06B3, D03D15, D01F1, E06B5