PHOTOPOLYMER FORMULATION FOR PRODUCING VISIBLE HOLOGRAMS

• US 20110236803A1
• Filed: 03/25/2011
• Published: 09/29/2011
• Est. Priority Date: 03/29/2010
• Status: Active Grant

• Current Assignee: Bayer Materialscience AG (Covestro AG)
• Original Assignee: Bayer Materialscience AG (Covestro AG)
• Inventors: Hönel, Dennis, Bruder, Friedrich-Karl, Rölle, Thomas, Fäcke, Thomas, Weiser, Marc-Stephan
• Granted Patent: US 9,281,000 B2
• Time in Patent Office: Days
• US Class Current: 430/2
• CPC Class Codes: C09B 57/00 Other synthetic dyes of known constitution
• CPC Class Codes: G03F 7/001 Phase modulating patterns, e.g. refractive index patterns
• CPC Class Codes: G03F 7/031 Organic compounds not covered by group G03F7/029
• CPC Class Codes: G03H 1/02 Details of features involved during the holographic process; Replication of holograms without interference recording
• CPC Class Codes: G03H 2001/0264 Organic recording material
• CPC Class Codes: G03H 2260/12 Photopolymer
• CPC Class Codes: G11B 7/24044 for storing optical interference patterns, e.g. holograms; for storing data in three dimensions, e.g. volume storage G11B7/24038 takes precedence

Abstract

The present invention relates to a photopolymer formulation containing chemically crosslinked matrix polymers, writing monomers and a photoinitiator system, wherein the photoinitiator system contains a HABI, a dye attuned to the HABI and having an absorption maximum in the range of 400-800 nm and a hydrogen donor. The present invention further relates to a process for producing exposed holographic media with the above photopolymer formulation.

Claims

1. A photopolymer formulation comprising chemically crosslinked matrix polymers, writing monomers and a photoinitiator system, wherein the photoinitiator system comprises a HABI, a dye attuned to the HABI and having an absorption maximum in the range of 400-800 nm, and a hydrogen donor.

2. The photopolymer formulation according to claim 1, wherein the HABI is a compound of formula (I)

3. The photopolymer formulation according to claim 2, wherein R², R³, R⁵, R⁶ are each a hydrogen radical.

4. The photopolymer formulation according to claim 1, wherein the hydrogen donor is selected from the group consisting of alkylamine, alkylaminoalcohol, substituted glyine ester, aromatic thiol, aliphatic thiol, aromatic amine, aliphatic amine, aromatic disulphide, benzylic disulphide, aromatic diselenide, and benzylic diselenide.

5. The photopolymer formulation according to claim 1, wherein the hydrogen donor is selected from the group consisting of 2-mercapto-1-methylimidazole, 1-phenyl-1H-tetrazole-5-thiol, mercaptobenzothiazole, phenyl disulphide, dodecanethiol, 2(3H)-benzoxazolethione, 1H-1,2,4-triazole-3-thiol, 5,5′

-dithiobis-1-phenyl-1H-tetrazole, 1-methyl-1H-tetrazole-5-thiol, 5-methyl-1,3,4-thiadiazole-2-thiol, N-phenylglycine ethyl ester, and N-phenylglycine methyl ester.

6. The photopolymer formulation according to claim 1, wherein the chemically crosslinked matrix polymers are polyurethanes.

7. The photopolymer formulation according to claim 1, wherein the writing monomers comprise a mono- and/or a multifunctional writing monomer.

8. The photopolymer formulation according to claim 7, wherein the mono and/or multifunctional writing monomer comprises a mono- and/or a multifunctional acrylate.

9. The photopolymer formulation according to claim 8, wherein the acrylate has the general formula (III)

10. The photopolymer formulation according to claim 1, further comprising urethanes as plasticizers,

11. The photopolymer formulation according to claim 10, wherein the urethanes are substituted with at least one fluorine atom.

12. The photopolymer formulation according to claim 10, wherein the urethanes have the general formula (IV)

13. The photopolymer formulation according to claim 11, wherein at least one of the radicals R⁹, R¹⁰, and/or R¹¹ is substituted with at least one fluorine atom.

14. The photopolymer formulation according to claim 12, wherein R⁹ is an organic radical having at least one fluorine atom.

15. A process for producing exposed holographic media, which comprises producing a holographic medium from a photopolymer formulation according to claim 1 and exposing a hologram into the medium using electromagnetic radiation.

16. The process according to claim 15, wherein the holographic media is selected from the group consisting of in-line holograms, off-axis holograms, full-aperture transfer holograms, white light transmission holograms, Denisyuk holograms, off-axis reflection holograms, edge-lit holograms, holographic stereograms.