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US4482389A Expired / Lapsed US ⏱️ 0.0 years remaining

Nacreous pigments

Assignee: Merck Patent GmbH
•
Filing: 1983-09-22
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Granted: 1984-11-13
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Expires: 2003-09-22
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Abstract

Abstract Nacreous pigments which have improved stability to weathering and are based on mica flakes coated with metal oxides, are provided with a stabilizing, chromium-containing second coating which comprises a combination of metal salts. To form the second layer, iron and/or manganese are deposited on the starting pigments in the form of the hydroxide, carbonate or phosphate and chromium is deposited on the starting pigments in the form of the hydroxide, carbonate or phosphate or as methacrylato-chromium chloride. These are prepared by adding iron and/or manganese and chromium, in the form of salt solutions and at a pH of 2 to 8, to an aqueous suspension of a mica flake pigment coated with metal oxides, precipitating them on the mica flake pigments, and separating off these pigments and drying them.

Inventors

  • 👤 Klaus-Dieter Franz
  • 👤 Klaus Ambrosius
  • 👤 Reiner Esselborn
  • 👤 Manfred Kieser

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 21:36
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/0015; C09C1/0021; C09C1/40; C01; C01P; C01P2004/00; C01P2004/80; C01P2004/82; C01P2004/84; C09C2200/00; C09C2200/10; C09C2200/102; C09C2200/30; C09C2200/301; C09C2200/40; C09C2200/401; C09C2220/00; C09C2220/10; C09C2220/106

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 82 words
A nacreous pigment having good weathering stability, comprising a mica flake substrate coated with a first metal oxide layer and, thereon, a second layer comprising a chromium salt and one or both of a manganese salt and an iron salt, wherein the iron and manganese are deposited on the first-layer-containing pigments in the form of the hydroxide, carbonate or phosphate and the chromium is deposited on the first-layer-containing pigments in the form of the hydroxide, carbonate or phosphate or as methacrylato-chromium chloride.
Claim 2
Dependent Claim 82 words
A nacreous pigment having good weathering stability, comprising a mica flake substrate coated with a first metal oxide layer and, thereon, a second layer comprising a chromium salt and one or both of a manganese salt and an iron salt, wherein the iron and manganese are deposited on the first-layer-containing pigments in the form of the hydroxide, carbonate or phosphate and the chromium is deposited on the first-layer-containing pigments in the form of the hydroxide, carbonate or phosphate or as methacrylato-chromium chloride.
Claim 3
Dependent Claim 16 words
A nacreous pigment of claim 1, wherein the second coating comprises 0.1-10% of the pigment weight.
Claim 4
Dependent Claim 24 words
A nacreous pigment of claim 1 wherein the content of chromium compound in the second coating is about 20 to about 80% by weight.
Claim 5
Dependent Claim 20 words
A nacreous pigment of claim 1 wherein the metals in the second layer are in the form of their phosphates.
Claim 6
Dependent Claim 28 words
A nacreous pigment of claim 1 wherein the iron or manganese is in the form of the phosphate and the chromium is in the form of methacrylato-chromium chloride.
Claim 7
Dependent Claim 26 words
A nacreous pigment of claim 1 wherein the second layer consists essentially of a chromium salt and one of a manganese salt and an iron salt.
Claim 8
Dependent Claim 20 words
A nacreous pigment of claim 1 wherein the first layer consists essentially of titanium or zirconium oxides or oxide hydrates.
Claim 9
Dependent Claim 23 words
A nacreous pigment of claim 1 wherein the diameter of the mica flakes is about 5-200 μm and their thickness is 0.1-5 μm.
Claim 10
Dependent Claim 65 words
A nacreous pigment of claim 1 prepared by a process comprising adding iron or manganese, and chromium, in the form of salt solutions and at a pH of 2 to 8, to an aqueous suspension of a mica flake pigment coated with a first metal oxide layer, precipitating the metal salts on the mica flake pigments and then separating off and drying the resultant pigments.
Claim 11
Dependent Claim 16 words
A nacreous pigment of claim 9, wherein the pH value is kept substantially constant at 4-7.
Claim 12
Dependent Claim 13 words
A nacreous pigment of claim 9 wherein the metal salts are precipitated together.
Claim 13
Dependent Claim 21 words
A nacreous pigment of claim 9 wherein the metal salts are precipitated by simultaneous addition of an alkali metal phosphate solution.
Claim 14
Dependent Claim 19 words
A nacreous pigment of claim 9 wherein the precipitation is carried out at a temperature of about 30°-70° C.
Claim 15
Dependent Claim 26 words
In a composition comprising a base ingredient and an effective amount of a nacreous pigment, the improvement wherein the nacreous pigment is that of claim 1.

References Cited (Backward Citations)

US3087828A Cited
US3087829A Cited
US3331699A Cited
US3342617A Cited
US3650790A Cited
US3832208A Cited
US3926659A Cited
US4134776A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-11-13 1988-05-14 1988-11-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-11-13 1992-05-14 1992-11-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-11-13 1996-05-14 1996-11-13 $7700.00 Window Closed / Lapsed

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