Photochromic compositions, preparation thereof and articles made therefrom or coated therewith

1. A cross-linkable photochromic composition, comprising:

at least one segmented or non-segmented polyurethane-type or polyurethane-urea-type linear polymer having at least one non-terminal moiety that comprises at least one unsaturated group; and

an effective amount of at least one photochromic organic compound to impart the desired photochromic tint to the matrix obtained by cross-linking the composition, wherein the unsaturated group of the non-terminal moiety enables the polyurethane-type or polyurethane-urea-type liner polymer to cross-link onto itself to form a matrix in which the photochromic organic compound is trapped.

2. The photochromic composition according to claim 1 , wherein the at least one unsaturated group of the non-terminal moiety of the linear polymer is of (meth)acrylic-type.

3. The photochromic composition according to claim 1 , wherein the at least one unsaturated group of the non-terminal moiety of the linear polymer is comprised in a pendant group.

4. The photochromic composition according to claim 1 , wherein the polyurethane-type linear polymer results from a reaction between at least one diol bearing at least one unsaturated group, and at least one diisocyanate.

5. The photochromic composition according to claim 4 , wherein the at least one unsaturated group of the at least one dial is a (meth)acrylic group.

6. The photochromic composition according to claim 1 , wherein the polyurea-type linear polymer results from a reaction between at least one diol bearing at least one unsaturated group, at least one diisocyanate, and at least one diamine.

7. The photochromic composition according to claim 6 , wherein the at least one unsaturated group of the diol is a (meth)acrylic group.

8. The photochromic composition according to claim 4 , wherein the at least one diol bearing at least one unsaturated group has a formula (I) below

in which:

R is a bivalent linking group selected from

C 2 -C 14 alkylene groups,

polyalkylerie oxide groups comprising up to 17 carbon atoms,

phenylene groups, which are non-substituted or substituted with C 1 -C 9 alkyls,

in which X is a phenylene or cyclohexyl group;

A is O, S, SO 2 , —CH 2 —, —C(CH 3 ) 2 — or —C(CH 3 )(C 6 H 5 )—; R 3 and R 4 independently represent a C 1 -C 4 alkyl group, a halogen; m and n are, independently, integers from 0 to 4;

R 1 and R 2 represent, independently, hydrogen or a methyl group;

x and y are integers from 0 to 2, the sum x+y being equal to 2.

9. The photochromic composition according to claim 8 , wherein when R represents

R 3 and R 4 independently represent a chlorine or bromine.

10. The photochromic composition according to claim 6 , wherein the at least one diol bearing at least one unsaturated group has a formula (I) below

in which:

R is a bivalent linking group selected from

C2-C14 ailcylene groups,

polyalkylene oxide groups comprising up to 17 carbon atoms,

phenylene groups, which are non-substituted or substituted with C 1 -C 9 alkyls,

in which X is a phenylene orcyclobexyl group;

A is O, S, SO 2 , —CH 2 —, —C(CH 3 ) 2 — or —C(CH 3 )(C 6 H 5 )—; R 3 and R 4 independently represent a C 1 -C 4 alkyl group, a halogen; m and n are, independently, integers from 0 to 4;

R 1 and R 2 represent, independently, hydrogen or a methyl group;

x and y are integers from 0 to 2, the sum x+y being equal to 2.

11. The photochromic composition according to claim 10 , wherein when R represents

R 3 and R 4 independently represent a chlorine or bromine.

12. The photochromic composition according to claim 1 , wherein the linear polymer is segmented and is obtained by

(i) a reaction between

at least one diol of formula (1) below:

 in which:

R is a bivalent linking group selected from

C2-C14 alkylene groups,

polyalkylene oxide groups comprising up to 17 carbon atoms,

phenylene groups, which are non-substituted or substituted with C 1 -C 9 alkyls,

in which X is a phenylene or cyclohexyl group;

A is O, S, SO 2 , —CH 2 —, —C(CH 3 ) 2 — or —C(CH 3 )(C 6 H 5 )—; R 3 and R 4 independently represent a C 1 -C 4 alkyl group, a halogen; m and n are, independently, integers from 0 to 4;

R 1 and R 2 represent, independently, hydrogen or a methyl group;

x and y are integers from 0 to 2, the sum x+y being equal to 2;

at least one long chain polyester or polyether diol;

optionally, at least one diamine; and

at least one diisocyanate;

or

(ii) a reaction between:

at least one diol of formula (I), as defined in (i) in this claim above;

at least one long chain diamine; and

at least one diisocyanate.

13. The photochromic composition according to claim 4 , wherein the reaction is stopped by adding at least one monofunctional alcohol or isocyanate.

14. The photochromic composition according to claim 6 , wherein the reaction is stopped by adding at least one monofunctional alcohol or isocyante.

15. The photochromic composition according to claim 1 , further comprising at least one additional unsaturated monomer.

16. The photochromic composition according to claim 15 , wherein the weight ratio between the unsaturated polyurethane-type or polyurea-type linear polymer and the unsaturated monomer ranges from 90/10 to 10/90.

17. A cross-linked photochromic composition obtainable by cross-linking a composition according to claim 1 .

18. A photochromic lens based on a cross-linked photochromic composition according to claim 17 .

19. A method of preparing a photochromic cornposition comprising mixing the following:

at least one polyurethane-type or polyurethane-urea-type linear polymer having at least one non-terminal moiety that comprises at least one unsaturated group;

an effective amount of at least one photochromic organic compound to impart the desired photochromic tint to the matrix obtained by cross-linking the composition, wherein the unsaturated group of the non-terminal moiety enables the polyurethane-type or polyurethane-urea-type linear volvmer to cross-link onto itself to form a matrix in which the photochromic organic compound is trapped;

optionally, at least one additional unsaturated monomer;

optionally, an effective amount of at least one radical polymerisation initiator; and

optionally, an effective amount of an inert solvent.

20. A cross-linkable photochromic coating composition, comprising:

at least one segmented or non-segmented polyurethane-type or polyurethane-urea-type linear polymer having at least one non-terminal moiety that comprises at least one unsaturated group; and

an effective amount of at least one photochromic organic compound to impart the desired photochromic tint to the matrix obtained by cross-linking the composition, wherein the unsaturated group of the non-terminal moiety enables the polyurethane-type or polyurerhane-urea-type linear polymer to cross-link onto itself to form a matrix in which the photochromic organic compound is trapped.