Pigments with improved sparkling effect
The present invention relates to pigments with improved and adjustable sparkling effect comprising A) a plate-like substrate of perlite coated with (a) dielectric material, and/or metal; and B) a plate-like substrate of mica, coated with (a) dielectric material, and/or a metal; and a process for their production and their use in paints, ink jet printing, for dyeing textiles, for pigmenting coatings (paints), printing inks, plastics, cosmetics, glazes for ceramics and glass. The pigments show an improved sparkle effect; in particular an attractive high sparkle intensity.
1. A sparkling effect pigment comprising:
A) a plate-like substrate of perlite coated with a dielectric material, wherein the dielectric material is a metal oxide selected from TiO 2 , ZrO 2 , Fe 2 O 3 , Fe 3 O 4 , Cr 2 O 3 , ZnO, or mixtures of said metal oxides; and
B) a plate-like substrate of mica, coated with a dielectric material, wherein the dielectric material is a metal oxide selected from TiO 2 , ZrO 2 , Fe 2 O 3 , Fe 3 O 4 , Cr 2 O 3 , ZnO, or mixtures of said metal oxides, and
wherein the coated plate-like substrate of perlite is contained in an amount of 1-80% by weight based on the sum of coated plate-like substrate of perlite and coated plate-like substrate of mica.
2. The sparkling effect pigment according to claim 1 wherein the coated plate-like substrate of mica with a medium particle size of 12 to 30 μm, is combined with the coated plate-like substrate of perlite with a medium particle size of 12 to 30 μm.
3. The sparkling effect pigment according to claim 1 , wherein the plate-like substrate of mica is a natural mica.
4. The sparkling effect pigment according to claim 1 , wherein the plate-like substrate of mica is a synthetic mica.
5. The sparkling effect pigment according to claim 1 , wherein the plate-like substrate of perlite and/or mica is coated with at least three alternating layers of high and low refractive index, and wherein the at least three alternating layers are TiO 2 /SiO 2 /TiO 2 , (SnO 2 )TiO 2 /SiO 2 /TiO 2 , (SnO 2 )TiO 2 /SiO 2 /(SnO 2 )TiO 2 , TiO 2 /SiO 2 /TiO 2 /SiO 2 /TiO 2 , Fe 2 O 3 /SiO 2 /TiO 2 , or TiO 2 /SiO 2 /Fe 2 O 3 .
6. The sparkling effect pigment according to claim 1 , wherein the pigment has the following layer structure:
perlite/mica
TiO 2
SiO 2
TiO 2
perlite/mica
TiO 2
SiO 2
Fe 2 O 3
perlite/mica
TiO 2
SiO 2
TiO 2 •Fe 2 O 3
perlite/mica
TiO 2
SiO 2
(Sn,Sb)O 2
perlite/mica
(Sn,Sb)O 2
SiO 2
TiO 2
perlite/mica
Fe 2 O 3
SiO 2
(Sn,Sb)O 2
perlite/mica
TiO 2 •Fe 2 O 3
SiO 2
TiO 2 •Fe 2 O 3
perlite/mica
TiO 2
SiO 2
MoS 2
perlite/mica
TiO 2
SiO 2
Cr 2 O 3
perlite/mica
Cr 2 O 3
SiO 2
TiO 2
perlite/mica
Fe 2 O 3
SiO 2
TiO 2
perlite/mica
TiO 2
Al 2 O 3
TiO 2
perlite/mica
Fe 2 TiO 5
SiO 2
TiO 2
perlite/mica
TiO 2
SiO 2
Fe 2 TiO 5 /TiO 2
perlite/mica
TiO 2
SiO 2
TiO 2 /SiO 2 /TiO 2 + Prussian
Blue
perlite/mica
TiO 2
SiO 2
TiO 2 /SiO 2 /TiO 2
perlite/mica
TiO 2 /SiO 2 /TiO 2
SiO 2
TiO 2 /SiO 2 /TiO 2
perlite/mica
(SnO 2 )TiO 2
SiO 2
(SnO 2 )TiO 2 .
7. The sparkling effect pigment according to claim 1 , wherein the pigment comprises a TiO 2 coated synthetic mica with a d 50 of about 25 μm and a TiO 2 coated perlite with a d 50 of about 20 μm, or the pigment comprises a TiO 2 coated synthetic mica with a d 50 of about 20 μm and a TiO 2 coated perlite with a d 50 of about 20 μm, or the pigment comprises a TiO 2 coated synthetic mica with a d 50 of about 40-60 μm and a TiO 2 coated perlite with a d 50 of about 20-30 μm; or the pigment comprises a TiO 2 coated mica with a d 50 of about 12 μm and a TiO 2 coated perlite with a d 50 of about 17 μm.
8. The sparkling effect pigment according to claim 1 , wherein the pigment comprises a Fe 2 O 3 coated synthetic mica based pigment with a d 50 of about 20-25 μm and a Fe 2 O 3 coated perlite based pigment with a d 50 of about 20 μm, or the pigment comprises a Fe 2 O 3 coated synthetic mica based pigment with a d 50 of about 40-60 μm and a Fe 2 O 3 coated perlite based pigment with a d 50 of about 20-30 μm.
9. A method of using the sparkling effect pigments according to claim 1 comprising incorporating the pigments in paints, ink-jet printing, for dyeing textiles, for pigmenting coatings, printing inks, plastics, cosmetics, glazes for ceramics and glass.
10. Paints, printing inks, plastics, cosmetics, ceramics and glass, which are pigmented with the sparkling effect pigment according claim 1 .
11. A process for the production of the sparkling effect pigments according to claim 1 , comprising
blending of a dielectric material coated plate-like substrate of perlite and of a dielectric material coated plate-like substrate of mica; or
blending of the uncoated plate-like perlite and mica substrates and
coating them in a chemical vapour deposition (CVD) or a wet-chemical process with one, or more layers of a dielectric material, and optionally starting the coating process with one of the substrates and adding the other in a later stage.
12. The sparkling effect pigment according to claim 3 , wherein the natural mica is muscovite mica.
13. The sparkling effect pigment according to claim 4 , wherein the synthetic mica is fluorophlogopite.
14. The sparkling effect pigment according to claim 1 , wherein the coated plate-like substrate of perlite is contained in an amount of 5-80% by weight based on the sum of coated plate-like substrate of perlite and coated plate-like substrate of mica.
15. The sparkling effect pigment according to claim 1 , wherein the coated plate-like substrate of perlite is contained in an amount of 10-50% by weight based on the sum of coated plate-like substrate of perlite and coated plate-like substrate of mica.
16. The sparkling effect pigment according to claim 1 , wherein the coated plate-like substrate of perlite is contained in an amount of 10-40% by weight based on the sum of coated plate-like substrate of perlite and coated plate-like substrate of mica.