3D structural siliceous color pigments

• US 6,756,115 B2
• Filed: 11/30/2001
• Issued: 06/29/2004
• Est. Priority Date: 11/30/2000
• Status: Expired due to Fees

• Current Assignee: EMD Chemicals Incorporated (EMD Biosciences Incorporated)
• Original Assignee: EM Industries, Inc.
• Inventors: Lewis, Diane, Fu, Guoyi
• Primary Examiner(s): Le, H. Thi
• Application Number:
  US09/997,286
• Publication Number:
  US 20030008771A1
• Time in Patent Office: 942 Days
• Field of Search: 428/402, 428/323, 428/331, 428/327, 428/328, 428/329, 428/332, 427/212, 427/189, 427/190
• US Class Current: 428/402
• CPC Class Codes: C01P 2002/30 Three-dimensional structures
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/32 Spheres
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2004/84 one phase coated with the other
• CPC Class Codes: C01P 2006/22 Rheological behaviour as dispersion, e.g. viscosity, sedimentation stability
• CPC Class Codes: C01P 2006/60 Optical properties, e.g. expressed in CIELAB-values
• CPC Class Codes: C09C 1/00 Treatment of specific inorganic materials other than fibrous fillers tenebrescent materials C09K9/00; luminescent materials C09K11/00; Preparation of carbon black
• CPC Class Codes: C09C 1/30 Silicic acid
• CPC Class Codes: C09C 1/3054 Coating
• CPC Class Codes: C09D 5/36 Pearl essence, e.g. coatings containing platelet-like pigments for pearl lustre
• CPC Class Codes: C09K 9/00 Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as a result of excitation by some form of energy
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/254 Polymeric or resinous material
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/257 Iron oxide or aluminum oxide
• CPC Class Codes: Y10T 428/259 Silicic material
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/2949 Glass, ceramic or metal oxide in coating
• CPC Class Codes: Y10T 428/2962 : Silane, silicone or siloxane in coating
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]

Abstract

The invention relates to particles with opalescent effect—especially 3-D structural color pigments-based on solid colloidal crystals of monodispersed spheres and the manufacturing processes suitable for large-scale production of such solid colloidal crystal products. The particles with opalescent effect contain a sphere based crystal structure (or super-lattice) built up by monodisperse spheres and one or more secondary types of much smaller colloidal particles occupying partially or completely the empty spaces between the monodisperse spheres.

Claims

1. A particle matrix with opalescent effect comprising monodisperse spheres and one or more secondary types of much smaller colloidal particles occupying partially or completely the empty spaces between the monodisperse spheres wherein the colloidal particles effectively adjust the refractive index ratio between the sphere and the media between them to achieve a predetermined color effect and bind the matrix together.

2. A particle matrix according to claim 1, wherein the size of the monodisperse spheres range from about 150 nm-about 450 nm.

3. A particle matrix according to claim 1, wherein the monodisperse spheres are transparent and comprise metal chalcogenide, metal pnictide, an organic polymer, or a metal oxide.

4. A particle matrix according to claim 1, wherein the size of the secondary colloid species ranges about 5 nm up to about one-third in diameter of the size of the monodisperse spheres.

5. A particle matrix according to claim 1, wherein the colloidal species comprise a metal oxide sol of SiO₂, Al₂O₃, TiO₂, SnO₂, Sb₂O₅, Fe₂O₃, ZrO₂, CeO₂ or Y₂O₃;

and/or metal colloid of gold, silver or copper; and

/or a colloidal polymer of poly(methyl methacrylate), poly(vinyl acetate), polyacrylonitrile or poly(styrene-co-butadiene).

6. A particle matrix to claim 1, wherein the colloidal species are present in an amount of from about 5%-by-weight to about 25%-by-weight with respect to the monodisperse spheres.

7. A particle matrix according to claim 1, wherein the particles show an opal structure.

8. A particle matrix according to claim 1, wherein the particles show an inverse opal structure.

9. A particle matrix according claim 1, wherein the particle matrix comprises thin layer crystals with a layer thickness from about 20 μ

m-about 5 mm.

10. A particle matrix according to claim 1, wherein the monodisperse spheres are silica spheres.

11. A particle matrix according to claim 1, wherein the monodisperse spheres have a particle size standard deviation of less than 5%.

12. A photonic and optoelectronic device comprising a particle matrix according to claim 1.

13. A method of manufacturing a thin layer of a particle matrix according to claim 1 by coating a substrate with monodisperse spheres.

14. A method according to claim 13, comprising preparing a suspension of monodisperse spheres at an effective concentration, in an effective solvent, and with an effective amount of one or more colloidal species with much smaller particle size than the monodisperse spheres.

15. A method according to claim 13, comprising depositing a suspension onto a flat substrate, static or constantly moving with desired thickness of the suspension layer and optionally the crystalline layer, and then initially drying and removing from the substrate small pieces of flakes.

16. A method according to claim 13, further comprising drying, optionally calcining, and milling to reduce the particle size to an appropriate range, and optionally classifying into different fractions of final products.

17. A method according to claim 13, wherein a concentration of a suspension of monodisperse spheres for crystallization is in the range from about 5%-by-weight-about 65%-by-weight.

18. A method according to claim 13, wherein the substrate comprises glass, a metal, or a polymer material.

19. A method according to claim 13, wherein the substrate surface is pretreated with dilute acids or bases in order to make it more wettable for the colloid suspension.

20. A method according to claim 13, wherein the substrate comprises stainless steel, aluminum, polypropylene, polystyrene, poly(methylpentene), polycarbonate, or poly(ethylene terephthalate).