Platelet-like substrates

• US 5,407,746 A
• Filed: 09/28/1993
• Issued: 04/18/1995
• Est. Priority Date: 07/06/1989
• Status: Expired due to Term

• Current Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Original Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Inventors: Dietz, Johann, Thurn-Muller, Angelika, Prengel, Constanze
• Primary Examiner(s): Lesmes, George F.
• Assistant Examiner(s): Copenheaver, Blaine R.
• Application Number:
  US08/127,532
• Time in Patent Office: 567 Days
• Field of Search: 428/403, 428/404, 428/363, 428/406, 424/63, 424/69, 106/415, 106/418, 106/467, 106/469, 106/DIG. 3, 106/436, 106/450
• US Class Current: 428/403
• CPC Class Codes: A61K 2800/412 Microsized, i.e. having sizes between 0.1 and 100 microns
• CPC Class Codes: A61K 2800/43 Pigments; Dyes
• CPC Class Codes: A61K 8/025 Explicitly spheroidal or spherical shape
• CPC Class Codes: A61K 8/0254 Platelets; Flakes
• CPC Class Codes: A61K 8/25 Silicon; Compounds thereof
• CPC Class Codes: A61K 8/29 Titanium; Compounds thereof
• CPC Class Codes: A61Q 1/02 Preparations containing skin colorants, e.g. pigments preparations in powder form A61Q1/12
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01P 2004/20 extending in two dimensions, e.g. plate-like
• CPC Class Codes: C01P 2004/32 Spheres
• CPC Class Codes: C01P 2004/54 Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension
• 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 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C01P 2004/80 Particles consisting of a mixture of two or more inorganic phases
• CPC Class Codes: C09C 1/0015 Pigments exhibiting interference colours, e.g. transparent platelets of appropriate thinness or flaky substrates, e.g. mica, bearing appropriate thin transparent coatings
• CPC Class Codes: C09C 1/0018 uncoated and unlayered plate-like particles
• CPC Class Codes: C09C 1/0021 comprising a core coated with only one layer having a high or low refractive index
• CPC Class Codes: C09C 1/30 Silicic acid
• CPC Class Codes: C09C 1/405 containing combined silica, e.g. mica
• CPC Class Codes: C09C 2200/1004 : the core comprising at least one inorganic oxide, e.g. Al2O3, TiO2 or SiO2
• CPC Class Codes: C09C 2200/102 : the core consisting of glass or silicate material like mica or clays, e.g. kaolin
• CPC Class Codes: C09C 2200/1054 : the core consisting of a metal
• CPC Class Codes: C09C 2200/1087 : the core consisting of bismuth oxychloride, magnesium fluoride, nitrides, carbides, borides, lead carbonate, barium or calcium sulfate, zinc sulphide, molybdenum disulphide or graphite
• CPC Class Codes: C09C 2200/505 : Inorganic particles, e.g. oxides, nitrides or carbides
• CPC Class Codes: Y10S 106/03 : Mica
• CPC Class Codes: Y10T 428/2911 : Mica flake
• CPC Class Codes: Y10T 428/2991 : Coated
• CPC Class Codes: Y10T 428/2993 : Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]
• CPC Class Codes: Y10T 428/2996 : Glass particles or spheres

Abstract

The application relates to deagglomerated and readily dispersible platelet-like substrates with a high degree of softness, which are characterized by a content of 0.5-20% by weight of spherical particles having a small diameter in comparison with the platelet-like substrate, and to a process for their preparation and their use.

Claims

1. A deagglomerated, readily dispersible platelet-shaped material comprising platelet-shaped substrates and coated thereon an amount of spherical particles sufficient to render the substrate readily dispersible and deagglomerated, wherein said platelet-shaped substrates have a maximum diameter of about 1 to about 500 μ

m and said spherical particles have a diameter from about 0.05 to about 50 μ

m and wherein the spherical particles exert a ball-bearing effect on the platelet-shaped substrates enabling the platelet-shaped substrates to move relative to one another.

2. A material of claim 1, comprising at least 0.5% by weight, based on the substrate, of spherical particles.

3. A material of claim 1, wherein the spherical particles are monodisperse SiO₂ or TiO₂.

4. A material of claim 3, wherein the spherical particles have a diameter of about 0.05 to 1.0 μ

m.

5. A material of claim 1, wherein the platelet-like substrate is a zeolite, glass, iron oxide, bismuth oxychloride, lead carbonate, barium sulfate or metal flakes.

6. A material of claim 1, wherein the substrate is mica, talc or mica coated with metal oxides.

7. A material of claim 1, wherein the platelet-shaped substrate is an inorganic material.

8. A material of claim 1, wherein the spherical particles are inorganic materials.

9. A material of claim 1, wherein the spherical particles are SiO₂, TiO₂, or ZrO₂.

10. A material of claim 1, wherein the substrate is additionally coated with a colorless or colored metal oxide or an oxide hydrate thereof.

11. A material of claim 1, wherein the substrate is additionally coated with chromium oxide or aluminum oxide or an oxide hydrate thereof.

12. A material of claim 1, further comprising a surfactant, gelatin or gel.

13. A process for the preparation of the material of claim 1, comprising mixing a suspension of a platelet-shaped substrate with a suspension of spherical particles having a small diameter in comparison with the platelet-shaped substrate, wherein both suspensions are acidic and optionally one or both contain surfactants, gelatin or a gel, and optionally the material is coated with metal oxide or an oxide hydrate thereof, isolating the material from the suspension by filtering, drying the material, and optionally subjecting it to calcination.

15. A material of claim 9, wherein the spherical particle is SiO₂ .

14. In an industrial formulation containing a platelet-shaped material, the improvement wherein said platelet-shaped material comprises a deagglomerated, readily dispersible platelet-shaped material comprising platelet-shaped substrates and coated thereon, an amount of spherical particles sufficient to render the substrate readily dispersible and deagglomerated, wherein said platelet-shaped substrates have a maximum diameter of about 1 to about 500 μ

m and said spherical particles have a diameter from about 0.05 to about 50 μ

m and wherein the spherical particles exert a ball-bearing effect on the platelet-shaped substrates enabling the platelet-shaped substrates to move relative to one another.

16. In a cosmetic preparation containing a platelet-shaped material, the improvement wherein said material comprises a deagglomerated, readily dispersible platelet-shaped material comprising platelet-shaped substrates and coated thereon, an amount of spherical particles sufficient to render the substrate readily dispersible and deagglomerated, wherein said platelet-shaped substrates have a maximum diameter of about 1 to about 500 μ

m and said spherical particles have a diameter from about 0.05 to about 50 μ

m and wherein the spherical particles exert a ball-bearing effect on the platelet-shaped substrates enabling the platelet-shaped substrates to move relative to one another.