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EP-4737534-A1 - LIGHTWEIGHT PHOSPHORESCENT STRIP

EP4737534A1EP 4737534 A1EP4737534 A1EP 4737534A1EP-4737534-A1

Abstract

A phosphorescent composition is provided. The composition includes clear polymer and phosphorescent pigment dispersed in the clear polymer. About 5% to about 40% of the phosphorescent pigment is loaded in the clear polymer.

Inventors

  • REBAR, Victoria
  • HOWARD, CHRIS
  • SUBLETT, Don

Assignees

  • Pexco Aerospace, Inc.

Dates

Publication Date
20260506
Application Date
20251021

Claims (15)

  1. A phosphorescent composition comprising: a clear polymer; and a phosphorescent pigment dispersed within the clear polymer, wherein about 5% to about 40% of the phosphorescent pigment is loaded in the clear polymer.
  2. The phosphorescent composition of claim 1, wherein the phosphorescent pigment comprises strontium aluminate.
  3. The phosphorescent composition of claims 1 or 2, wherein the clear polymer comprises polycarbonate, an acrylic, or a combination thereof.
  4. The phosphorescent composition of any one of claims 1 to 3, wherein about 5% to about 30% of the phosphorescent pigment is loaded in the clear polymer.
  5. The phosphorescent composition of any one of claims 1 to 3, wherein about 10% to about 20% of the phosphorescent pigment is loaded in the clear polymer.
  6. A phosphorescent assembly comprising: a reflective layer (104); and a phosphorescent layer (102) arranged over the reflective layer (104), the phosphorescent layer (102) comprising the phosphorescent composition of any one of claims 1 to 5.
  7. The phosphorescent assembly of claim 6, wherein the phosphorescent layer (102) has a thickness (t) between about 35 mils and 50 mils.
  8. The phosphorescent assembly of claim 6 or 7, further comprising an adhesive (108) arranged between the reflective layer (104) and the phosphorescent layer (102), the adhesive (108) being clear.
  9. The phosphorescent assembly of any one of claims 6 to 8, wherein the phosphorescent layer (102) has an area weight of between 100 mg/cm 2 and 200 mg/cm 2 .
  10. The phosphorescent assembly of any one of claims 6 to 9, further comprising support structures (106) arranged on a backside of the reflective layer (104), the support structures (106) protruding from the backside of the reflective layer (104) and being spaced apart from one another throughout a length of the phosphorescent layer (102).
  11. The phosphorescent assembly of claim 10, wherein the support structures (106) are arranged along a central portion of the reflective layer (104), wherein the backside of the reflective layer (104) comprises an adhesive (108) in contact with the support structures (106).
  12. The phosphorescent assembly of claim 10 or 11, wherein the support structures (106) are configured to rest within a bottom surface of a cavity (112), sidewalls of the cavity being defined by flooring (110).
  13. The phosphorescent assembly of claim 12, wherein outer sidewalls of the phosphorescent layer (102) are configured to contact the sidewalls of the cavity (112).
  14. The phosphorescent assembly of claim 12, wherein outer portions (116) of the phosphorescent layer (102) are configured to overlie upper surfaces of the flooring (110) that define the cavity (112) and that are adjacent to the cavity (112).
  15. A method comprising: forming the phosphorescent composition of any one of claims 1 to 5 by dispersing a phosphorescent pigment within the clear polymer; forming the phosphorescent composition into an elongated strip; attaching a reflective layer (104) to a bottom surface of the elongated strip to form a phosphorescent assembly; and arranging the phosphorescent assembly into a cavity (112) of flooring (110).

Description

Related Applications This application claims the benefit of U.S. Provisional Patent Application No. 63/713,458 filed on October 29, 2024. Field of Invention The present invention relates generally to phosphorescent strips used as emergency lighting that have a reduced weight. Background Emergency lighting in buildings, transportation, and even on roadways are vital in the event of an emergency where power is lost. Examples of emergency lighting include battery-operated lights, generator-operated lights, phosphorescent paints, and phosphorescent decals. In the aircraft industry, for example, passengers escaping a dark plane may be guided down the aisle and to the nearest emergency exit through phosphorescent illuminated strips on or near the floor. Summary of Invention According to one aspect, a phosphorescent composition is provided. The composition includes a clear polymer and phosphorescent pigment dispersed in the clear polymer. About 5% to about 40% of the phosphorescent pigment is loaded in the clear polymer. The clear polymer may include polycarbonate, and the phosphorescent pigment may include strontium aluminate. According to another aspect, a phosphorescent strip is provided. The strip includes a phosphorescent layer arranged over a reflective layer. The phosphorescent layer is made from a phosphorescent composition that includes a clear polymer loaded with about 5% to about 40% of phosphorescent pigment. According to yet another aspect, a phosphorescent assembly for a flooring cavity is provided. The phosphorescent assembly includes a phosphorescent layer arranged over a reflective layer. The phosphorescent layer is made from a phosphorescent composition that includes a clear polymer and a phosphorescent pigment. The assembly further includes support portions extending from a bottom surface of the reflective layer and spaced apart along a length of the reflective layer. The assembly is configured to cover a cavity having sidewalls defined by flooring. At least outer portions of the phosphorescent layer may overlie upper surfaces of the flooring. The support portions are configured to extend into the cavity and contact a bottom surface of the cavity to support central portions of the phosphorescent layer. The foregoing and other features of the application are described below with reference to the drawings. Brief Description of the Drawings FIGURE 1 illustrates some embodiments of a cross-sectional view of a phosphorescent assembly as described herein.FIGURE 2 illustrates some embodiments of a phosphorescent assembly comprising support structures.FIGURE 3 illustrates some embodiments of a cross-sectional view of the phosphorescent assembly of FIGURE 2.FIGURE 4 illustrates some other embodiments of a phosphorescent assembly comprising support structures.FIGURE 5 illustrates some embodiments of a cross-sectional view of the phosphorescent assembly arranged within a flooring cavity.FIGURES 6, 7, 8, 9, and 10 illustrate some other embodiments of a cross-sectional view of the phosphorescent assembly arranged within a flooring cavity. Detailed Description In the airplane industry, a plane's aisle may be illuminated with lighting that runs along the length of the aisle flooring and/or that runs perpendicular to the length of the aisle flooring to guide passengers to exits. The lighting may comprise a rubber material loaded with phosphorescent pigments configured to glow in dark conditions. To protect the phosphorescent pigment and rubber material from wear, such as wear from passenger shoes and suitcases, the rubber material is encased by several other support layers. The support layers add weight to the airplane and also may complicate reproduction and replacement of the lighting. Thus, various embodiments of the present application provide a phosphorescent strip system that provides sufficient luminescence with less materials to reduce the system's weight while also simplifying manufacturing and installation of the system. The principles of the present application relate to a phosphorescent strip, such as for use in airplanes for emergency lighting, and thus will be described below in this context. It will be appreciated that the principles of the application may be applicable to other industries that utilize emergency lighting applications, such as in stairs, aisles, or hallways in office buildings, residential apartments, theaters, other types transportation (e.g., trains, busses, ships), etc. Turning now to Fig. 1, a phosphorescent strip is shown generally. The strip may comprise a phosphorescent layer 102 arranged over a reflective layer 104. The phosphorescent layer 102 comprises a phosphorescent composition, which includes a phosphorescent pigment dispersed within a clear polymer. In some embodiments, the clear polymer comprises polycarbonate, an acrylic, or the like. The clear polymer may also contain a blend of several polymers, such as a blend of polycarbonate and acrylic. The phosphorescent pi