Optical article comprising a temporary antifog coating based on sorbitan surfactants

Patent metadata

Field	Value
Publication number	US-9494713-B2
Application number	US-201114351327-A
Country	US
Kind code	B2
Filing date	Oct 14, 2011
Priority date	Oct 14, 2011
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

An optical article includes a substrate having a main surface coated with an antireflection coating and, directly contacting the antireflection coating, a precursor coating of an antifog coating obtained through the grafting on the antireflection coating of at least one compound B bearing a polyoxyalkylene group, the coating precursor of the antifog coating being coated with a surfactant film so as to form an antifog coating. The surfactant film contains at least one surfactant A having a sorbitan ring hydroxyl groups functionalized with OH-terminated polyoxyalkylene groups and R1 groups of formula:—(R d O) z —(Y) n2 —R′, in which R d is an alkylene group, z is an integer >1, Y is a divalent group, n2 is 0 or 1 and R′ is a saturated hydrocarbon group having 12 to 19, preferably 13 to 19 carbon atoms. Surfactants A provide a visual indication whether or not the antifogging effect will still be long-lasting.

First claim

The invention claimed is:

1. An optical article comprising a substrate having at least one main surface coated with an antireflection coating and, directly contacting said antireflection coating, a precursor coating of an antifog coating obtained through the grafting on said antireflection coating of at least one compound B bearing a polyoxyalkylene group, said coating precursor of the antifog coating being coated with a surfactant film so as to form an antifog coating, characterized in that said surfactant film contains at least one surfactant A having a sorbitan ring with n of its four hydroxyl groups functionalized with the same or different OH-terminated polyoxyalkylene groups, and p of its four hydroxyl groups functionalized with the same or different R 1 groups of formula:
—(R d O) z —(Y) n2 —R′

in which R d is an alkylene group, z is an integer≧1, Y is a divalent group, n2 is 0 or 1 and R′ is a saturated hydrocarbon group having from 12 to 19 carbon atoms, n and p being integers such that n=2 or 3 and p=1 or 2 with n+p=4.

2. The optical article of claim 1 , wherein compound B bearing a polyoxyalkylene group is an organosilane having at least one silicon atom bearing at least one hydrolyzable group.

3. The optical article of claim 1 , wherein the antireflection coating has an outer surface bearing silanol groups.

4. The optical article according to claim 1 , wherein the surfactant film is formed by applying onto the coating precursor of the antifog coating a liquid solution containing at least one surfactant A.

5. The optical article of claim 4 , wherein the liquid solution comprises from 0.5 to 15%, by weight of surfactants A, relative to the weight of said solution.

6. The optical article according to claim 1 , wherein n2=1 and Y is a carbonyl group.

7. The optical article according to claim 1 , wherein surfactant A is a polyoxyethylene sorbitan fatty acid ester.

8. The optical article according to claim 1 , wherein surfactant A is a compound of formula (IX):

in which R a , R b , R c and R d independently represent linear or branched alkylene groups, w, x, y and z independently represent integers ≧1, and R′ is as previously defined.

9. The optical article according to claim 1 , wherein R′ is a saturated hydrocarbon group comprising from 14 to 18 carbon atoms.

10. The optical article according to claim 1 , wherein the total number of oxyalkylene groups present in the structure of surfactant A ranges from 4 to 40.

11. The optical article according to claim 1 , wherein the coating precursor of the antifog coating has a thickness lower than or equal to 5 nm.

12. The optical article according to claim 1 , wherein compound B is a compound of formula:
R 11 Y′ m Si(X) 3-m   (I)

in which the Y′ groups, being the same or different, are monovalent organic groups bound to the silicon through a carbon atom, the X groups, being the same or different, are hydrolyzable groups, R 11 is a group comprising a polyoxyalkylene group, and m is an integer equal to 0, 1 or 2.

13. The optical article according to claim 1 , further defined as an ophthalmic lens.

14. An optical article comprising a substrate having at least one main surface coated with an antireflection coating, and directly contacting said antireflection coating a precursor coating of an antifog coating, wherein said antireflection coating displays a residual color when no surfactant film is applied onto said coating precursor of the antifog coating and a modified residual color when a film of a surfactant capable of modifying the residual color displayed by said antireflection coating is applied onto said coating precursor of the antifog coating,
characterized in that said coating precursor of the antifog coating is coated with a film of surfactant capable of modifying the residual color displayed by said antireflection coating so as to form an antifog coating.

15. A method for determining whether a spectacle lens exhibits antifog properties and, if needed, imparting antifog properties to said spectacle lens, comprising:
providing a spectacle lens comprising a substrate having at least one main surface coated with an antireflection coating, and directly contacting said antireflection coating a precursor coating of an antifog coating, wherein said antireflection coating displays a residual color when no surfactant film is applied onto said coating precursor of the antifog coating and a modified residual color when a film of a surfactant capable of modifying the residual color displayed by said antireflection coating is applied onto said coating precursor of the antifog coating,
determining visually which residual color is displayed by said antireflection coating, and
if at least part of the antireflection coating does not display the modified residual color, applying an additional amount of surfactant capable of modifying the residual color displayed by said antireflection coating on said at least part of the coating precursor of the antifog coating so as to restore the antifog properties of the spectacle lens.

16. The optical article of claim 2 , wherein the antireflection coating has an outer surface bearing silanol groups.

17. The optical article of claim 1 , wherein R′ is a saturated hydrocarbon group having from 13 to 19 carbon atoms.

18. The optical article of claim 4 wherein the liquid solution comprises from 2 to 8% by weight of surfactants A, relative to the weight of said solution.

19. The optical article according to claim 1 , wherein R′ is a saturated hydrocarbon group comprising from 15 to 17 carbon atoms.

20. The optical article according to claim 1 , wherein the total number of oxyalkylene groups present in the structure of surfactant A ranges from 8 to 30.

Assignees

• Cretier Annette
• Saint-Lu Charlotte
• Essilor Int

Inventors

• Cretier Annette
• Saint-Lu Charlotte

Classifications

• G02B1/04 Primary

  made of organic materials, e.g. plastics (G02B1/08 takes precedence) · CPC title

• Y10T428/31663

  As siloxane, silicone or silane · CPC title

• G02B1/111

  using layers comprising organic materials · CPC title

• C08L71/02

  Polyalkylene oxides · CPC title