Holographic storage medium comprising polyfunctional epoxy monomers capable of undergoing cationic polymerization

1. A compound represented by the following structural formula:

wherein:

each group R 7 is an unsubstituted aliphatic group, a substituted aliphatic group, an unsubstituted aryl group, a substituted aryl group;

each group R 8 is R 9 , hydrogen, an alkenyl, a substituted or unsubstituted C 1-12 alkyl, C 1-12 cycloalkyl, aryl substituted C 1-12 -alkyl or aryl or R z —(O—Y 1 ) m —, (R z ) 3 Si—(O—Si(R z ) 2 ) q —Y 1 — or (R z ) 3 Si—(O—Si(R z ) 2 ) q —O—;

each R 9 is independently represented by the following structural formula:

wherein:

X 1 and X 2 are independently an inert linking group;

each R a is independently a substituted or unsubstituted aliphatic group or a substituted or unsubstituted aryl group;

each R b is an aliphatic group substituted with an epoxide;

each R z is independently a substituted or unsubstituted C 1-12 alkyl group, C 1-12 cycloalkylalkyl group, aryl substituted C 1-12 alkyl group or aryl group;

each Y 1 is independently a C 1-12 alkylene group;

m is an integer from 1 to 10; and q is an integer from 0 to 4.

2. The compound of claim 1 wherein:

each R 7 is independently a substituted or unsubstituted C 1-12 alkyl, C 1-12 cycloalkyl, aryl substituted C 1-12 alkyl or aryl group;

each R 9 is represented by

each group R 10 is independently a substituted or unsubstituted C 1-12 alkylene, C 1-12 cycloalkylene, C 1-12 arylalkylene, or arylene group, —Y 1 —[O—Y 1 ] p —, —Y 1 —Si(R z ) 2 —Y 1 —, —Y 1 —Si(R z ) 2 —Y 1 —O—Y 1 —Si(R z ) 2 —Y 1 —, or —Y 1 —Si(R z ) 2 —Y 1 —Si(R z ) 2 —Y 1 —;

each R z is independently a C 1-12 alkyl group;

each Y 1 is independently a C 1-12 alkylene group;

each group R 11 and R 12 is independently a substituted or unsubstituted C 1-12 alkyl, C 1-12 cycloalkyl, aryl substituted C 1-12 alkyl group or aryl group; and

each group R 13 is independently an epoxide substituted aliphatic group having from 2–10 carbon atoms.

3. The compound of claim 2 wherein:

R 8 is substituted or unsubstituted C 1-12 alkylsilane, C 1-12 cycloalkylsilane, C 1-12 alkoxysilane, arylsubstituted C 1-12 alkyl silane or a substituted or unsubstituted 1-alkenyl group or a substituted or unsubstituted C 1-12 n-alkenyl group where n is greater than or equal to 1;

R 10 is independently a C 1-12 alkylene, C 1-12 cycloalkylene, C 1-12 arylalkylene, or arylene group.

4. The compound of claim 3 wherein at least one group R 13 comprises a cycloalkene oxide.

5. The compound of claim 4 wherein each R 13 is represented by the following structural formula:

6. The compound of claim 3 wherein:

R 7 is a methyl group,

R 8 is ethenyl or R 9 ;

each R 9 is

each group R 10 is —(CH 2 ) 2 —, —(CH 2 ) 6 — or —(CH 2 ) 8 —;

each group R 11 and R 12 are a methyl group; and each group R 13 is a 2-(3,4-epoxycyclohexyl) ethyl group.

7. A holographic recording medium comprising:

a) at least one polyfunctional epoxide monomer or oligomer represented by the following structural formula:

wherein:

each group R 7 is an unsubstituted aliphatic group, a substituted aliphatic group, an unsubstituted aryl group, a substituted aryl group;

each group R 8 is R 9 , hydrogen, an alkenyl, a substituted or unsubstituted C 1-12 alkyl, C 1-12 cycloalkyl, aryl substituted C 1-12 -alkyl or aryl or R z —(O—Y 1 ) m —, (R z ) 3 Si—(O—Si(R z ) 2 ) q —Y 1 — or (R z ) 3 Si—(O—Si(R z ) 2 ) q —O—;

each R 9 is independently represented by the following structural formula:

wherein:

X 1 and X 2 are independently an inert linking group;

each R a is independently a substituted or unsubstituted aliphatic group or a substituted or unsubstituted aryl group;

each R b is an aliphatic group substituted with an epoxide;

each R z is independently a substituted or unsubstituted C 1-12 alkyl group, C 1-12 cycloalkylalkyl group, aryl substituted C 1-12 alkyl group or aryl group;

each Y 1 is independently a C 1-12 alkylene group;

m is an integer from 1 to 10; and q is an integer from 0 to 4;

b) a binder which is capable of supporting cationic polymerization;

c) an acid generator capable of producing an acid upon exposure to actinic radiation; and optionally

d) a sensitizer.

8. The holographic recording medium of claim 7 , additionally comprising a difunctional epoxide monomer.

9. The holographic recording medium of claim 7 , additionally comprising a monofunctional epoxide monomer.

10. The holographic recording medium of claim 7 wherein:

each R 7 is independently a substituted or unsubstituted C 1-12 alkyl, C 1-12 cycloalkyl, aryl substituted C 1-12 alkyl or aryl group;

each R 9 is represented by

each group R 10 is independently a substituted or unsubstituted C 1-12 alkylene, C 1-12 cycloalkylene, C 1-12 arylalkylene, or arylene group, —Y 1 —[O—Y 1 ] p —, —Y 1 —Si(R z ) 2 —Y 1 —, —Y 1 —Si(R z ) 2 —Y 1 —O—Y 1 —Si(R z ) 2 —Y 1 —, or —Y 1 —Si(R z ) 2 —Y 1 —Si(R z ) 2 —Y 1 —;

each R z is independently a C 1-12 alkyl group;

each Y 1 is independently a C 1-12 alkylene group;

p is an integer from 1 to 5;

each group R 11 and R 12 is independently a substituted or unsubstituted C 1-12 alkyl, C 1-12 cycloalkyl, aryl substituted C 1-12 alkyl group or aryl group; and

each group R 13 is independently an epoxide substituted aliphatic group having from 2–10 carbon atoms.

11. The holographic recording medium of claim 10 wherein:

R 8 is substituted or unsubstituted C 1-12 alkylsilane, C 1-12 cycloalkylsilane, C 1-12 alkoxysilane, arylsubstituted C 1-12 alkyl silane or a substituted or unsubstituted 1-alkenyl group or a substituted or unsubstituted C 1-12 n-alkenyl group where n is greater than or equal to 1;

R 10 is independently a C 1-12 alkylene, C 1-12 cycloalkylene, C 1-12 arylalkylene, or arylene group.

12. The holographic recording medium of claim 11 wherein at least one group R 13 comprises a cycloalkene oxide.

13. The holographic recording medium of claim 12 wherein each R 13 is represented by the following structural formula:

14. The holographic recording medium of claim 13 wherein:

R 7 is a methyl group,

R 8 is -ethenyl or R 9 ;

each R 9 is

each group R 10 is —(CH 2 ) 2 —, —(CH 2 ) 6 — or —(CH 2 ) 8 —;

each group R 11 and R 12 are a methyl group; and

each group R 13 is a 2-(3,4-epoxycyclohexyl) ethyl group.

15. The holographic recording medium of claim 8 wherein the difunctional epoxide monomer is represented by the following structural formula:

R 24 Si(R 25 ) 2 OSi(R 26 ) 2 R 24

where each group R 24 is a 2-(3,4-epoxycyclohexyl)ethyl grouping; each grouping R 25 is a methyl group, and each group R 26 is a methyl group.

16. The holographic recording medium of claim 8 wherein the holographic medium comprises between about 0.25 to about 5 parts by weight of the difunctional epoxide monomer per part by weight of the polyfunctional epoxide monomer.

17. The holographic recording medium of claim 7 wherein the holographic medium comprises from about 90 parts binder and 10 parts monomer or oligomer (w/w) to about 10 parts binder and 90 parts monomer or oligomer (w/w).

18. The holographic recording medium of claim 7 wherein the acid generator capable of producing an acid upon exposure to actinic radiation is a diaryliodonium salt.

19. A holographic recording medium of claim 7 wherein the sensitizer is 5,12-bis(phenylethynyl)naphthacene.