Claims
- 1. A composition comprising:
(a) a polymer matrix component that is substantially non-absorbing in the visible region of the electromagnetic spectrum and having dispersed therein:
(i) particle scattering colorant particles; and (ii)at least one luminescent substance; wherein said particle scattering colorant particles:
(1) are selected from the group consisting of a semiconductor, metallic conductor, metal oxide or metal salt; (2) have an average diameter in the smallest dimension of less than about 0.1 micron; (3) have a minimum in the transmitted light intensity ratio in the 380 to 750 nanometer range that is shifted at least by 10 nanometers compared with that obtained for the same semiconductor, metallic conductor, metal oxide or metal salt having an average particle size above about 20 microns; and wherein said luminescent substance further comprises at least one fluorescent substance, at least one phosphorescent substance or at least one fluorescent and at least one phosphorescent substance.
- 2. A composition comprising at least one first composition and at least one second composition, and a luminescent substance dispersed within at least one of said first and said second compositions, said first composition comprising a solid first matrix component in which there is dispersed a non-liquid particle scattering colorant and, said second composition comprising a solid second matrix component in which there is dispersed an electronic transition colorant, dye or pigment;
said first and second compositions being located relative to one another such that said first composition is either disposed on and substantially exterior to said second composition on at least a part thereof or said first and second compositions are substantially mutually interpenetrating; wherein:
(a) there exists at least one incident visible light wavelength and one incident light angle such that said first composition absorbs less than about 90% of light incident on said first composition; (b) the absorption coefficient of said first composition is less than about 50% of that of said second composition at a wavelength in the visible region of the spectrum; (c) the highest absorption peak of the particle scattering colorant does not fall in the visible region of the spectrum; (d) either (i) said particle scattering colorant has a refractive index that matches that of said first matrix component at a wavelength in the visible region of the electromagnetic spectrum and has an average particle size of less than about 2000 microns, or (ii) the average refractive index of said particle scattering colorant differs from that of said first matrix component by at least about 5% in the visible region of the spectrum, the average particle size of said particle scattering colorant in the smallest dimension is less than about 2 microns, and said particle scattering colorant, when dispersed in a colorless, isotropic liquid having a substantially different refractive index, is characterized at wavelengths in the visible region of the spectrum as having an effective maximum absorbance that is at least about 2 times its effective minimum absorbance; and (e) said luminescent substance comprises at least one fluorescent substance or at least one phosphorescent substance or at least one fluorescent and at least one phosphorescent substance.
- 3. The composition of claim 1 wherein said particle scattering colorant particles comprise a metallic conductor selected from the group consisting of gold, platinum, copper, aluminum, lead, palladium, silver, rhodium, osmium, iridium, and alloys thereof; said particle scattering colorant particles have an average diameter in the smallest dimension of less than about 0.2 microns; said polymer matrix component is substantially non-absorbing in the visible region of the spectrum; and said particle scattering colorant has a minimum in the transmitted light intensity ratio in the 380 to 750 nanometer range that is shifted at least by 10 nanometers compared with that obtained for the same metallic conductor having an average particle size above about 20 microns.
- 4. The composition of claim 3 wherein said particle scattering colorant particles comprise colloidal particles.
- 5. The composition of claim 4 wherein the transmitted light intensity ratio of said particle scattering colorant has two minima in the visible wavelength region of the electromagnetic spectrum and the particle size distribution of said particle scattering colorant approaches a mononodal distribution.
- 6. The composition of claim 2 wherein said at least one first composition either absorbs or scatters more than about 50% of uniform radiation at the ultraviolet wavelength at which said at least one second composition undergoes the maximum rate of color fading.
- 7. The composition of claim 2 wherein said particle scattering colorant is substantially non-absorbing in the visible region of the electromagnetic spectrum.
- 8. The composition of claim 2 wherein the refractive index of said particle scattering colorant is substantially different than that of said first matrix component at all wavelengths in the visible region of the electromagnetic spectrum and wherein at least about 50% of all particles of said particle scattering colorant have a smallest dimension that is less than about 0.25 microns.
- 9. The composition of claim 2, wherein for said particle scattering colorant:
(a) the average particle size is from about 0.001 to about 0.4 microns; (b) the average ratio of maximum dimension to minimum dimension for individual particles is less than about four; and (c) the refractive index is substantially different than that of the matrix at all wavelengths in the visible region of the electromagnetic spectrum.
- 10. The composition of claim 2 wherein:
(a) the average particle size of said particle scattering colorant is less than about 1000 microns; (b) both said first matrix component and said particle scattering colorant are substantially optically isotropic; (c) there exists a wavelength in the visible region of the electromagnetic spectrum at which the refractive index of said first matrix component substantially equals that of said particle scattering colorant; (d) the refractive index difference of said first matrix component and said particle scattering colorant is substantially dependent on wavelength in the visible range of the electromagnetic spectrum; and (e) said first matrix composition is substantially non-absorbing at wavelengths in the visible region of the electromagnetic spectrum.
- 11. The composition of claim 10 wherein said particle scattering colorant and said first matrix component each exhibit refractive indices nF and nC, at 486.1 nm and 656.3 nm respectively, and wherein the difference in nF−nC for said particle scattering colorant and said first matrix component is greater in absolute magnitude than 0.001.
- 12. The composition of claim 2 wherein said first and second matrix components comprise organic polymers.
- 13. The composition of claim 1 or claim 2 wherein said matrix component of claim 1 and at least one of said first and second matrix components of claim 2 comprises at least one material selected from the group consisting of homopolymers and copolymers of polyamide, polyester, polyolefin, polyvinyl, acrylic, polysulfone, polycarbonate, polyarylate and polystyrene.
- 14. The composition of claim 2 wherein said first matrix component and said second matrix component are substantially mutually interpenetrating and wherein there exists a value αeveVe for said second composition and αsvsVs for said first composition differ by less than a factor of ten at a wavelength in the visible region of the electromagnetic spectrum; wherein αe is the absorption coefficient for said electronic transition colorant; αs is the effective absorption coefficient for said particle scattering colorant; vs and ve are, respectively, the volumes of said at least one first and second compositions; and Vs and Ve are respectively the volume fraction of said at least one first composition that is said particle scattering colorant and the volume fraction of said at least one second composition that is said electronic transition colorant.
- 15. An article comprising the composition of claim 2 wherein said at least one first composition comprises a layer disposed on and is substantially exterior to a layer of said second matrix composition on at least one side of said article; said at least one second composition comprises an electronic transition colorant or a pigment; there exists a wavelength of visible light and a light incidence angle at which from about 10% to about 90% light transmission occurs through said at least one first composition; and there is a value for said at least one second composition calculated as αeteVe that is greater than 0.1; wherein αe is the absorption coefficient at the wavelength in the visible region of the electromagnetic spectrum at which the maximum absorption occurs for said electronic transition colorant or said pigment; te is a maximum thickness of said layer comprising said at least one second composition; and Ve is the volume fraction of said at least one second composition comprising said electronic transition colorant or pigment.
- 16. An article comprising the composition of claim 1 or claim 2 wherein said article comprises at least one filament, at least one fiber or at least one filament and at least one fiber.
- 17. The article of claim 16 wherein said at least one first composition forms a fiber sheath that substantially covers a core that comprises said second matrix component.
- 18. The article of claim 17 wherein said sheath and said core have differing cross-sectional shapes.
- 19. The article of claim 18 in which the maximum ratio of orthogonal axial dimensions in cross-section for an outer surface of said sheath is less than about one-half of the corresponding ratio for said core.
- 20. The article of claim 17 where said sheath and said core both have a maximum ratio of orthogonal axial dimensions in cross-section that exceeds two and the long axis directions in cross-section of said sheath and said core are unaligned.
- 21. The article according to claim 17 comprising a plurality of said fibers and sheaths and exhibiting spatially dependent coloration or coloration a result of size and shape variations in the cross-section of said sheath or the cross-section of said core.
- 22. An article comprising the composition of claim 2 in which said particle scattering colorant in said at least one first composition comprises an inorganic composition.
- 23. The article of claim 22 wherein said inorganic composition comprises at least one material selected from the group consisting of bismuth oxychloride, titanium dioxide, antimony trioxide, barium titanate, solid solutions of BaTiO3 with SrTiO3, PbTiO3, BaSnO3, CaTiO3, or BaZrO3, potassium lithium niobate, aluminum hydroxide, zirconium oxide, colloidal silica, lithium niobate, lithium tantalite, proustite; zinc oxide, alpha-zinc sulfide, and beta-zinc sulfide.
- 24. An article comprising the composition of claim 1 or claim 2 wherein said particle scattering colorant comprises a ferroelectric, antiferroelectric, or photoferroelectric material.
- 25. An article comprising the composition of claim 1 wherein said article is in the form of a film or plate in which a layer of said at least one first composition is joined to either one side or to both opposite sides of said at least one second composition.
- 26. An article comprising the composition of claim 2 wherein said article is in the form of a film or plate comprising at least one layer of each of said first composition and said second composition, provided that at least one layer of said first composition is present as a top or outer layer of said film or plate.
- 27. The article of claim 25 or claim 26 in the form of a light source, visual display, sign, or switchable screen, and comprising a particle scattering colorant, an electronic transition colorant, or a matrix that is switchable in either refractive index or absorption coefficient.
- 28. The article of claim 26 wherein in the composition of claim 2 said first matrix component and said second matrix component both comprise an organic polymer.
- 29. The article of claim 26 wherein in the composition of claim 2 said solid first matrix component comprises a polymer matrix, and the refractive index difference between said polymer matrix and either said particle scattering colorant or said electronic transition colorant undergoes substantial change at a wavelength in the visible spectra as a result of one or more of a temperature change, humidity change, an electric field, integrated thermal exposure, or exposure to either light or actinic radiation.
- 30. The article of claim 29 wherein said electronic transition colorant contains a photochromic anil, fulgide, or spiropyran.
- 31. The composition of claim 2 comprising either an electronic transition colorant or a matrix polymer that displays electronic transition coloration, wherein dichroism in the visible range of the electromagnetic spectrum results from either preferential orientation of said electronic transition colorant or said matrix polymer.
- 32. The article of claim 16 wherein the effective diameter of said filament is in the range of from about 0.01 to 3 mm.
- 33. The composition of claim 1 or claim 2 wherein at least one luminescent response is produced by a wavelength in the infrared region of the electromagnetic spectrum.
- 34. The composition of claim 1 or claim 2 wherein at least one luminescent response is produced by a wavelength in the visible region of the electromagnetic spectrum.
- 35. The composition of claim 1 or claim 2 wherein at least one luminescent response is produced by a wavelength in the ultraviolet region of the electromagnetic spectrum.
- 36. The composition of claim 1 or claim 2 wherein luminescent responses are produced by at least two excitation wavelengths selected from different members of the group consisting of the infrared, visible, and ultraviolet region of the electromagnetic spectrum.
- 37. The composition of claim 2 in which said particle-scattering colorant comprises a gas.
- 38. The composition of claim 37 wherein said gas is air.
- 39. The composition of claim 1 or claim 2, wherein said particle scattering colorant has an average particle size of less than 3 microns and comprises a plurality of layers, each of said layers having a different refractive index.
- 40. The particle of claim 39 wherein the refractive index difference is greater than about 5%.
- 41. The composition of claim 1 or claim 2 comprising at least one each of a fluorescent and a phosphorescent material.
- 42. The composition of claim 2 wherein said luminescent substance is dispersed in said first composition, said second composition or both.
- 43. The composition of claim 42 wherein said luminescent substance is dispersed in said first composition.
- 44. The composition of claim 42 wherein said luminescent substance is dispersed in said second composition.
- 45. The composition of claim 1 or claim 2 wherein said fluorescent or phosphorescent material is represented by the formula Zn1−xCdxS, wherein x is greater than zero and no greater than unity, said fluorescent or phosphorescent material further comprising at least one trace element selected from the group consisting of Cu, Ag, or Mn.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of U.S. patent application Ser. No. 09/758,534, filed Jan. 10, 2001, which is a division of U.S. patent application Ser. No. 08/535,687, filed Sep. 28, 1995, now U.S. Pat. No. 5,932,309, the entire disclosures of which are hereby incorporated by reference.
Divisions (2)
|
Number |
Date |
Country |
Parent |
09758534 |
Jan 2001 |
US |
Child |
10266362 |
Oct 2002 |
US |
Parent |
08535687 |
Sep 1995 |
US |
Child |
09758534 |
Jan 2001 |
US |