Phosphorous containing glass having antimicrobial efficacy

Patent metadata

Field	Value
Publication number	US-9708216-B2
Application number	US-201414548650-A
Country	US
Kind code	B2
Filing date	Nov 20, 2014
Priority date	Nov 26, 2013
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A strengthened antimicrobial glass including greater from about 50.0 mol. % to about 65.0 mol. % SiO 2 , about 14.0 mol. % to about 22.0 mol. % Al 2 O 3 , about 14.0 mol. % to about 22.0 mol. % R 2 O, wherein R is an alkali metal, and about 4.0 mol. % to 10.0 mol. % P 2 O 5 . The glass may have a compressive stress layer having a thickness of greater than or equal to about 20 μm to less than or equal to about 60 μm and having a compressive stress of greater than or equal to about 700 MPa. The glass may have an antimicrobial activity greater than or equal to about 1.0 log kill at about 23° C. and about 40.0% relative humidity. A method for making the glass may include obtaining a glass article, strengthening the glass article by contact with a first ion-exchange liquid, and contacting the glass article with second ion-exchange liquid comprising an antimicrobial agent.

First claim

What is claimed is:

1. A strengthened antimicrobial glass comprising:
greater than or equal to about 50.0 mol. % to less than or equal to about 65.0 mol. % SiO 2 ;
greater than or equal to about 14.0 mol. % to less than or equal to about 22.0 mol. % Al 2 O 3 ;
greater than or equal to about 14.0 mol. % to less than or equal to about 22.0 mol. % R 2 O, wherein R is an alkali metal; and
greater than or equal to about 4.0 mol. % to less than or equal to about 10.0 mol. % P 2 O 5 , wherein:
the glass comprises a compressive stress layer having a thickness of greater than or equal to about 20 μm and having a surface compressive stress of greater than or equal to about 700 MPa; and
the glass as an antimicrobial activity greater than or equal to about 1.0 Log Kill at about 23° C. and about 40.0% relative humidity.

2. The glass of claim 1 , wherein the glass comprises Ag.

3. The glass of claim 2 , wherein the glass has a maximum concentration of Ag within 60 nm of a free surface of the glass.

4. The glass of claim 2 , wherein an average concentration of Ag within 60 nm of a free surface of the glass is greater than or equal to about 10 mol. % to less than or equal to about 15 mol. %.

5. The glass of claim 2 , wherein the glass has a light transmission of greater than or equal to about 85% over wavelengths from greater than or equal to about 400 nm to less than or equal to about 750 nm.

6. The glass of claim 1 , wherein the glass has a molar ratio of Al 2 O 3 to R 2 O that is greater than or equal to about 0.5:1 to less than or equal to about 1.5:1.

7. The glass of claim 1 , wherein the glass further comprises greater than 0.0 mol. % to less than or equal to about 4.0 mol. % ZnO.

8. The glass of claim 1 , wherein the glass has an antimicrobial activity greater than or equal to about 5.0 Log Kill at about 37° C. and a relative humidity greater than or equal to about 90%.

9. The glass of claim 1 , wherein R is selected from the group consisting of Li, Na, and K.

10. The glass of claim 1 , wherein the compressive stress layer has a depth greater than or equal to about 40 μm to less than or equal to about 50 μm.

11. The glass of claim 10 , wherein the glass has a compressive stress of greater than or equal to about 900 MPa.

12. The glass of claim 1 , further comprising greater than 0.0 mol. % to less than or equal to about 4.0 mol. % alkaline earth metal.

13. The glass of claim 1 , further comprising a fluorosilane coating on a free surface of the glass.

14. The glass of claim 13 , wherein the coating has a general formula of:
A x -Si—B 4-x , where

A is selected from the group consisting of perfluoroalkyl, perfluoroalkyl terminated perfluoropolyether, perfluoroalkyl-alkyl, copolymers of fluoroalkene silanes and alkene silanes, and mixtures of fluoroalkylsilanes and hydrophilic silanes; and
B is selected from the group consisting of Cl, acetoxy, and alkoxy; and
x=1 or 2.

15. A method for making strengthened antimicrobial glass, the method comprising:
obtaining a glass article comprising:
greater than or equal to about 50.0 mol. % to less than or equal to about 65.0 mol. % SiO 2 ,
greater than or equal to about 14.0 mol. % to less than or equal to about 22.0 mol. % Al 2 O 3 ,
greater than or equal to about 14.0 mol. % to less than or equal to about 22.0 mol. % R 2 O, wherein R is an alkali metal, and
greater than or equal to about 4.0 mol. % to less than or equal to about 10.0 mol. % P 2 O 5 ;

strengthening the glass article by contact with a first ion-exchange liquid; and
contacting the glass article with a second ion-exchange liquid comprising an antimicrobial agent, wherein:
the glass comprises a compressive stress layer having a thickness of greater than or equal to about 20 μm to less than or equal to about 60 μm and having a compressive stress of greater than or equal to about 700 MPa; and
the glass has an antimicrobial activity greater than or equal to about 1.0 log kill at about 23° C. and a relative humidity of about 40%.

16. The method of claim 15 , wherein the first ion-exchange liquid is selected from the group consisting of NaNO 3 , KNO 3 , and mixtures thereof.

17. The method of claim 15 , wherein the antimicrobial agent comprises Ag.

18. The method of claim 17 , wherein the second ion-exchange liquid further comprises a member selected from the group consisting of NaNO 3 , KNO 3 , and mixtures thereof.

19. The method of claim 17 , wherein a silver salt concentration in the second ion exchange liquid is greater than or equal to about 5.0 mol. %.

20. The method of claim 15 , wherein the strengthening step comprises holding the glass article in a bath of the first ion-exchange liquid that has a temperature greater than or equal to about 300° C. to less than or equal to about 500° C. for a duration of greater than or equal to about 40 minutes to less than or equal to about 6 hours.

Assignees

• Corning Inc

Inventors

• Bookbinder Dana Craig
• Borrelli Nicholas Francis
• Dejneka Matthew John
• Gross Timothy Michael

Classifications

• C03C4/00

  Compositions for glass with special properties · CPC title

• Y10T428/31612

  As silicone, silane or siloxane · CPC title

• A01N59/00

  Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds · CPC title

• C03C3/097

  containing phosphorus, niobium or tantalum · CPC title

• C03C17/30

  with silicon-containing compounds · CPC title