Glass flake and coated glass flake

Patent metadata

Field	Value
Publication number	US-9237994-B2
Application number	US-200913058090-A
Country	US
Kind code	B2
Filing date	Aug 26, 2009
Priority date	Aug 27, 2008
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

A glass flake ( 10 ) having improved heat resistance and chemical resistance is formed from a glass base material satisfying, in mass %, 60≦SiO 2 ≦75, 5<Al 2 O 3 ≦15, 3≦CaO≦20, 6≦Na 2 O≦20 and 9≦(Li 2 O+Na 2 O+K 2 O)≦13. When 9≦(Li 2 O+Na 2 O+K 2 O)≦13 is satisfied in mass %, the CaO content and the Na 2 O content are preferably set within the ranges of 5≦CaO≦20 and 6≦Na 2 O≦13, respectively. When 13≦(Li 2 O+Na 2 O+K 2 O)≦20 is satisfied in mass %, the CaO content and the Na2O content are preferably set within the ranges of 3≦CaO≦15 and 9≦Na 2 O≦20, respectively. The working temperature of the glass base material is preferably 1180° C.-1300° C. The temperature difference AT obtained by taking the devitrification temperature of the glass base material from the working temperature of the glass base material is preferably 0° C.-200° C. The glass transition temperature of the glass base material is preferably 550° C.-700° C. The acid resistance index ΔW of the glass base material is preferably 0.05-1.5 mass %.

First claim

The invention claimed is:

1. A glass flake being characterized in that the glass flake is formed from a glass base material having a composition expressed in percent by mass of:
60≦SiO 2 ≦75;

10.11≦Al 2 O 3 ≦15;

5≦CaO≦20;

6≦Na 2 O≦13; and

9≦(Li 2 O+Na 2 O+K 2 O)≦13,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

2. The glass flake according to claim 1 , wherein a working temperature for glass, which is the temperature when the viscosity of molten glass is 100 Pa·sec (1000P), is 1180° C. to 1300° C.

3. The glass flake according to claim 1 , wherein the working temperature of the glass base material, is the temperature when the viscosity of molten glass is 100 Pa·sec (1000P).

4. The glass flake according to claim 1 , wherein a glass transition temperature of the glass base material is 550° C. to 700° C.

5. The glass flake according to claim 1 , wherein ΔW, which is a mass decrease rate measured by immersing the glass base material in a sulfuric acid aqueous solution for 72 hours at 80° C. and representing an index for acid resistance of the glass base material, is 0.05 to 1.5 percent by mass.

6. A coated glass flake according to claim 1 further comprising:
a coating that covers a surface of the glass flake, the coating having a main component of metal or metal oxide.

7. The coated glass flake according to claim 6 , being characterized in that the coating produces a metallic color or an interference color.

8. A method for fabricating the glass flake according to claim 1 , the method comprising:
melting and then crushing a glass base material of which composition, as expressed in percent by mass, is:
60≦SiO 2 ≦75;

10.11≦Al 2 O 3 ≦15;

5≦CaO≦20;

6≦Na 2 O≦13; and

9≦(Li 2 O+Na 2 O+K 2 O)≦13,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

9. A glass base material for forming the glass flake according to claim 1 , wherein the glass base material has a composition as expressed in percent by mass of:
60≦SiO 2 ≦75;

10.11≦Al 2 O 3 <15;

5≦CaO≦20;

6≦Na 2 O≦13; and

9≦(Li 2 O+Na 2 O+K 2 O)≦13,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

10. The glass flake according to claim 1 , being characterized in that the glass flake is for a coated glass flake that produces a metallic color or an interference color.

11. A glass flake being characterized in that the glass flake is formed from a glass base material having a composition expressed in percent by mass of:
60≦SiO 2 ≦68;

11.33≦Al 2 O 3 ≦15;

3≦CaO≦15;

9≦Na 2 O≦20; and

13<(Li 2 O+Na 2 O+K 2 O)≦20,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

12. A method for fabricating the glass flake according to claim 11 , the method comprising:
melting and then crushing a glass base material of which composition, as expressed in percent by mass, is:
60≦SiO 2 ≦68;

11.33≦Al 2 O 3 ≦15;

3≦CaO≦15;

9≦Na 2 O≦20; and

13<(Li 2 O+Na 2 O+K 2 O)≦20,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

13. A glass base material for forming the glass flake according to claim 11 , wherein the glass base material has a composition as expressed in percent by mass of:
60≦SiO 2 ≦68;

11.33≦Al 2 O 3 ≦15;

3≦CaO≦15;

9≦Na 2 O≦20; and

13<(Li 2 O+Na 2 O+K 2 O)≦20,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

14. A coated glass flake comprising:
the glass flake according to claim 11 ; and
a coating that covers a surface of the glass flake, the coating having a main component of metal or metal oxide.

15. A glass flake is formed from a glass base material having a composition expressed in percent by mass comprising:
63≦SiO 2 ≦75;

10.11≦Al 2 O 3 ≦15;

5≦CaO≦20;

6≦Na 2 O≦13; and

9≦(Li 2 O+Na 2 O+K 2 O)≦13,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

16. A glass flake is formed from a glass base material having a composition expressed in percent by mass comprising:
63≦SiO 2 ≦68;

11.33≦Al 2 O 3 ≦15;

3≦CaO≦15;

9≦Na 2 O≦20; and

13<(Li 2 O+Na 2 O+K 2 O)≦20,

wherein the content of Fe 2 O 3 is 0.5 percent by mass or less, and the content of ZnO is 2 percent mass or less, a temperature difference ΔT obtained by subtracting a devitrification temperature from a working temperature of the glass base material is 0° C. to 200° C. to suppress devitrification during glass formation, and wherein the glass flake is homogeneous and free from crystallized agglomerates.

17. The coated glass flake of claim 15 further comprising:
a coating that covers a surface of the glass flake, the coating having a main component of metal or metal oxide.

18. The coated glass flake of claim 16 further comprising:
a coating that covers a surface of the glass flake, the coating having a main component of metal or metal oxide.

Assignees

• Fujiwara Kosuke
• Koyama Akihiro
• Nippon Sheet Glass Co Ltd

Inventors

• Fujiwara Kosuke
• Koyama Akihiro

Classifications

• A61K8/02

  characterised by special physical form · CPC title

• C03C12/00

  Powdered glass (C03C8/02 takes precedence); Bead compositions · CPC title

• A61K8/29

  Titanium; Compounds thereof · CPC title

• A61Q1/10

  for eyes, e.g. eyeliner, mascara · CPC title

• C03C17/23

  Oxides (C03C17/02 takes precedence) · CPC title