Holographic recording medium

Abstract

A holographic recording medium has a recording layer, including a matrix formed of a polymer of spiroorthoester of an epoxy compound, a radical-polymerizable compound, and a photoinitiator.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a cross-sectional view showing a transmission holographic recording medium according to an embodiment;

FIG. 2 is a schematic diagram showing a transmission holographic recording-reconstructing apparatus according to an embodiment; and

FIG. 3 is a graph showing reconstructed signals of the holographic recording medium of Example 1 to which angular multiplexing recording has been performed.

Claims

1. A holographic recording medium, comprising a recording layer comprising: a matrix formed of a polymer of a spiroorthoester of an epoxy compound;a radical-polymerizable compound; anda photoinitiator.

2. The medium according to claim 1, wherein the spiroorthoester of the epoxy compound is a reaction product of the epoxy compounds and a lactone.

3. The medium according to claim 1, wherein the epoxy compound has an alkylene chain having 4 to 8 carbon atoms.

4. The medium according to claim 1, further comprising a curing agent.

5. The medium according to claim 4, wherein the curing agent is an organic acid anhydride.

6. The medium according to claim 1, further comprising a curing accelerator.

7. The medium according to claim 1, further comprising a cationic polymerization accelerator.

8. The medium according to claim 1, wherein cationic polymerization accelerator comprises a material selected from the group consisting of a sulfonium salt, an ammonium salt, a phosphonium salt, and an aluminum silanol complex.

9. The medium according to claim 1, wherein the recording medium has durometer hardness ranging A45 or more and A85 or less.

10. The medium according to claim 1, wherein the radical-polymerizable compound is contained in the recording layer in a ratio of 1 to 50% by weight.

11. The medium according to claim 1, wherein the photoinitiator is contained in the recording layer in a ratio of 0.1 to 10% by weight.

12. The holographic recording medium according to claim 1, wherein the recording layer is sandwiched between a pair of transparent substrates.

13. The medium according to claim 2, wherein the spiroorthoester of the epoxy compound is selected from the group consisting of the compounds represented by the following formulas: