Colored effect pigments

Patent metadata

Field	Value
Publication number	US-10689518-B2
Application number	US-201515328999-A
Country	US
Kind code	B2
Filing date	Jun 29, 2015
Priority date	Jul 25, 2014
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

The present invention relates to colored effect pigments, in particular to those containing an organic color pigment layer, to a preparation method thereof and to the use of these pigments especially in a composition comprising the colored effect pigments.

First claim

The invention claimed is:

1. A colored effect pigment, comprising a flaky metal substrate and at least three layers covering the flaky metal substrate, wherein the at least three layers comprise a layer package composed of layers a, b and c in the following sequence:
(a) a hydrated metal oxide primer layer comprising a hydrated metal oxide, wherein layer (a) consists of a sublayer (a 1 ) and a sublayer (a 2 ), wherein sublayer (a 1 ) is closest to the flaky metal substrate and consists of one or more hydrated metal oxides, and wherein sublayer (a 2 ) is between sublayer (a 1 ) and layer (b) and is composed of a mixture of a hydrated metal oxide and an organic color pigment of organic color pigment layer (b),
(b) an organic color pigment layer on layer (a) consisting of one or more organic color pigments and optionally acid groups, and
(c) a hydrated metal oxide layer on layer (b) comprising a hydrated metal oxide.

2. The colored effect pigment according to claim 1 , wherein layer (a) comprises a hydrated metal oxide of an element selected from the group consisting of aluminum, zinc, calcium, magnesium, zirconium and cerium.

3. The colored effect pigment according to claim 1 , wherein the total thickness of layer (a) is in the range of 1 to 50 nm.

4. The colored effect pigment according to claim 1 , wherein the amount of hydrated metal oxide, calculated as metal oxide, in layer (a) is from 0.1 to 20 percent by weight, based on the weight of the flaky metal substrate.

5. The colored effect pigment according to claim 1 , wherein the organic color pigment contained in layer (b) is insoluble in water.

6. The colored effect pigment according to claim 1 , wherein the organic color pigment contained in layer (b) is phthalocyanine, a metal phthalocyanine compound, an indigo compound or an anthradione compound.

7. The colored effect pigment according to claim 1 , wherein the thickness of layer (b) is in the range of 1 to 500 nm.

8. The colored effect pigment according to claim 1 , wherein the amount of organic color pigment in layer (b) is from 0.1 to 100 percent, based on the weight of the flaky metal substrate.

9. The colored effect pigment according to claim 1 , wherein layer (c) comprises at least one hydrated metal oxide of an element selected from the group consisting of aluminum, zinc, calcium, magnesium, zirconium, cerium and silicon.

10. The colored effect pigment according to claim 1 , wherein at least one protective layer (d) is located on top of layer (c).

11. The colored effect pigment according to claim 1 , wherein the flaky metal substrate comprises at least one metal or alloy selected from the group consisting of aluminum, titanium, gold, silver, iron, copper, zinc, tin, nickel and chromium.

12. The colored effect pigment according to claim 11 , wherein the metal alloy is a stainless steel.

13. The colored effect pigment according to claim 1 , wherein the flaky metal substrate is of aluminum or aluminum alloy.

14. The colored effect pigment according to claim 1 , wherein the flaky metal substrate is passivated by one or more passivation layers.

15. The colored effect pigment according to claim 1 , wherein the flaky metal substrate is pre-coated with at least one interference layer.

16. The colored effect pigment according to claim 15 , wherein the interference layer comprises at least one oxide or hydrated oxide of an element selected from the group consisting of titanium, iron, aluminum, zirconium, cerium, zinc, chromium, cobalt, tin, silicon and boron.

17. A manufacturing method for the colored effect pigment according to claim 1 , comprising the following steps:
(A) providing a suspension of a flaky metal substrate, optionally coated with one or more passivation layers and/or with at least one interference layer, in an aqueous medium;
(B) adding an aqueous solution of a metal salt to the suspension prepared in step (A) while keeping a prescribed pH value at a value necessary for precipitation of the corresponding hydrated metal oxide on the flaky metal substrate (neutralization point);
(C) decreasing the pH value obtained in step (B) to a range of from 0.2 to 3.0 below the neutralization point of the corresponding hydrated metal oxide;
(D) adding an acidic solution of an organic color pigment to the suspension prepared in step (C), thereby producing an intermediate pigment having a colored surface layer; and
(E) adding an aqueous solution of a metal salt to the suspension prepared in step (D) while adjusting the pH value to a value necessary for precipitation of the corresponding hydrated metal oxide (neutralization point) on the colored surface layer of the intermediate pigment obtained in step (D).

18. The manufacturing method for the colored effect pigment according to claim 17 , wherein the pigment achieved in step (E) is dried at a temperature in the range of from 100 to 200° C.

19. The manufacturing method for the colored effect pigment according to claim 17 , wherein the acidic organic color pigment solution is an acidic solution of phthalocyanine, a metal phthalocyanine compound, an indigo compound or an anthradione compound.

20. The manufacturing method for the colored effect pigment according to claim 19 , wherein the acidic organic color pigment solution is a sulfuric acid solution of phthalocyanine or of a metal phthalocyanine compound.

21. The manufacturing method for the colored effect pigment according to claim 17 , wherein the hydrated metal oxide in step (B) comprises a hydrated metal oxide of the elements selected from the group consisting of aluminum, zinc, calcium, magnesium, zirconium, or cerium.

22. The manufacturing method for the colored effect pigment according to claim 17 , wherein the hydrated metal oxide of the elements in step (E) comprises at least one type of hydrated oxides of the elements selected from the group consisting of aluminum, zinc, calcium, magnesium, zirconium, cerium and silicon.

23. A composition comprising the colored effect pigment according to claim 1 .

24. A composition according to claim 23 , which is a paint, ink, plastic film, plastic shaped body, coating, pigment, anticounterfeiting product or cosmetic composition.

25. An article which comprises a composition according to claim 24 , which is an ink, paint or coating composition, applied onto the surface of a plastic, paper, wooden or metallic substrate.

26. A method for the coloring of a paint, ink, plastic film, plastic shaped body, coating, pigment, anticounterfeiting product or cosmetic composition, which comprises incorporating a colored effect pigment according to claim 1 into the composition.

27. A method according to claim 26 , wherein the composition is an ink, paint or coating composition, and the method further comprises applying the ink, paint or coating composition onto the surface of a plastic, paper, wooden or metallic substrate.

28. The colored effect pigment according to claim 1 , wherein sublayer (a 1 ) consists of one hydrated metal oxide.

Assignees

• Merck Patent Gmbh

Inventors

• Li Bangyin
• Nakamura Nobuaki
• Koyama Kaoru

Classifications

• C09C1/0078 Primary

  Pigments consisting of flaky, non-metallic substrates, characterised by a surface-region containing free metal · CPC title

• C09D7/60 Primary

  non-macromolecular (C09D7/41-C09D7/48 take precedence) · CPC title

• C09C1/66

  Copper alloys, e.g. bronze · CPC title

• C09D7/70

  characterised by shape, e.g. fibres, flakes or microspheres · CPC title

• C09D7/62

  modified by treatment with other compounds · CPC title