Holographic recording material

Abstract

New photosensitive acrylic material compositions for fabrication of holographic recording materials (HRMs) are provided. These compositions are comprised of polymerizable acrylic monomers and light absorbing dyes, and when polymerized they are thermally stable, light sensitive, hard and inert to common chemicals. Methods of fabricating HRMs with symmetric concentration distribution of the dye are also provided.

We claim:  
     
         1 . A holographic recording material comprising of at least two distinctive polymerizable acrylic materials, each distinctive polymerizable acrylic material has a secondary carbon chain of a different length, and when the polymerizable acrylic materials are polymerized, the polymerized acrylic material remains thermally stable; and a dye selected from the group consisting of:  
       
         
           
           
               
               
           
         
         wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8  is a H, R 9 , or X,  
         R 9  is an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, an d X is a halogen;  
         
           
             
             
                 
                 
             
           
         
         wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , is a H, R 9 , or X;  
         R 9  is an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, and X is a halogen; and  
         combinations thereof.  
       
     
     
         2 . The holographic recording material of  claim 1  wherein at least two distinctive polymerizable acrylic materials are selected from the group consisting of:  
       
         
           
           
               
               
           
         
         wherein R′=H; or an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R=an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms;  
         .R 2 ″—O—R—O—R 1 ″.  
         wherein R=an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R 1 ″ and R 2 ″=—OC (═O)C(R 3 )═CH 2  or H, wherein R 3 =H, an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms;  
         
           
             
             
                 
                 
             
           
         
         wherein R=a tri- or tetra-substituted aryl group; or a carbon atom;  
         R′=H, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, R 1 , R 2 , and R 3 =—OC(═O)C(R 4 )═CH 2 or H wherein R 4 =H, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms; and  
         
           
             
             
                 
                 
             
           
         
         wherein R=a tri- or tetra-substituted aryl group; or a carbon atom;  
         R′=H, an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R 1 ′=R 2 ′=R 3 ′=—CH 2 CH 2 — or —CH 2 CH 2 CH 2 —, R 4 ′=R 5 ′=R 6 ′=—OC(═O)C(R 7 ′)═CH 2  or H wherein R 7 ′=H; or an alkyl 28 having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms.  
       
     
     
         3 . The holographic recording material of  claim 1  wherein the dye is 2-methyl-9,10-phenanthrenequinone.  
     
     
         4 . The holographic recording material of  claim 1  wherein the dye is 9,10-phenanthrenequinone.  
     
     
         5 . The holographic recording material of  claim 1  wherein the dye is 4H-cyclopenta[def]phenanthrene-8,9-dione.  
     
     
         6 . The holographic recording material of  claim 1  wherein the dye is 4,4-dimethylcyclopenta[def]phenanthrene-8,9-dione.  
     
     
         7 . The holographic recording material of  claim 1  wherein the dye comprises of 75 to 95 weight percent of 9,10-phenanthrenequinone and 25 to 5 weight percent of 9-iodophenanthrene.  
     
     
         8 . The holographic recording material of  claim 1  wherein the dye is selected from the group consisting of 2-methyl-9,10-phenanthrenequinone, 9,10-phenanthrenequinone, 4H-cyclopenta[def]phenanthrene-8,9-dione, 4,4-dimethylcyclopenta[def]phenanthrene-8,9-dione, and combinations thereof.  
     
     
         9 . The holographic recording material of  claim 1  wherein the ratio between each distinctive polymerizable acrylic material ranges from 1:99 to 99:1 percent by weight.  
     
     
         10 . The holographic recording material of  claim 1  wherein the polymerizable acrylic material polymerizes in a temperature range of 60° C. to 170° C.  
     
     
         11 . The holographic recording material of  claim 1  wherein the dye is about 0.2 to 5 weight percent of the acrylic material.  
     
     
         12 . A holographic recording medium comprising: 
 an inner layer comprising at least two distinctive polymerizable acrylic materials, and a dye selected from the group consisting of:                          wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8  is a H, R 9 , or X,    R 9  is an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, and X is a halogen;                          wherein R 1 , R 2  R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , is a H, R 9 , or X;    R 9  is an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, and X is a halogen; and    combinations thereof; and    an outer layer comprising a third polymerizable acrylic material wherein the dye material from the inner layer penetrates into the outer layers to form a concentration distribution of the dye material with the highest dye concentration in the inner layer and a lower concentration in outer layer of holographic recording medium.    
     
     
         13 . The holographic recording medium of  claim 12  wherein the at least two distinctive polymerizable acrylic materials and the third polymerizable acrylic material are selected from the group consisting of:  
       
         
           
           
               
               
           
         
         wherein R′=H; or an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R=an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms;  
         R 2 ″—O—R—O—R 1 ″ 
         wherein R=an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R 1 ″ and R 2 ″=—OC(═O)C(R 3 )═CH 2  or H, wherein R 3 =H, an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms;  
         
           
             
             
                 
                 
             
           
         
         wherein R=a tri- or tetra-substituted aryl group; or a carbon atom;  
         R′=H, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, R 1 , R 2 , and R 3 =—OC(═O)C(R 4 )═CH 2  or H wherein R 4 =H, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms; and  
         
           
             
             
                 
                 
             
           
         
         wherein R=a tri- or tetra-substituted aryl group; or a carbon atom;  
         R′=H, an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R 1 ′=R 2 ′=R 3 ′=—CH 2 CH 2 — or —CH 2 CH 2 CH 2 —, R 4 ′=R 5  ′R 6 ′=—OC(═O)C(R 7 ′)═CH 2  or H wherein R 7 ′=H; or an alkyl having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms.  
       
     
     
         14 . The holographic recording medium of  claim 12  wherein the dye is 2-methyl-9,10-phenanthrenequinone.  
     
     
         15 . The holographic recording medium of  claim 12  wherein the dye is 9,10-phenanthrenequinone.  
     
     
         16 . The holographic recording material of  claim 12  wherein the dye is 4H-cyclopenta[def]phenanthrene-8,9-dione.  
     
     
         17 . The holographic recording material of  claim 12  wherein the dye is 4,4-dimethylcyclopenta[def]phenanthrene-8,9-dione.  
     
     
         18 . The holographic recording material of  claim 12  wherein the dye comprises of 75 to 95 weight percent of 9,10-phenanthrenequinone and 25 to 5 weight percent of 9-iodophenanthrene.  
     
     
         19 . The holographic recording material of  claim 12  wherein the dye is selected from the group consisting of 2-methyl-9,10-phenanthrenequinone, 9,10-phenanthrenequinone, 4H-cyclopenta[def]phenanthrene-8,9-dione, 4,4-dimethylcyclopenta[def]phenanthrene-8,9-dione, and combinations thereof.  
     
     
         20 . The holographic recording material of  claim 12  wherein the ratio between each distinctive polymerizable acrylic material ranges from 1:99 to 99:1 percent by weight.  
     
     
         21 . The holographic recording material of  claim 12  wherein the polymerizable acrylic material polymerizes in a temperature range between 60° C. to 170° C.  
     
     
         22 . The holographic recording material of  claim 12  wherein the dye is about 0.2 to 5 weight percent of the at least two distinctive polymerizable acrylic materials.  
     
     
         23 . A method of fabricating a holographic recording medium comprising the steps of: 
 preparing an inner layer of at least two distinctive polymerizable acrylic materials and a dye selected from the group consisting of:                          wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8  is a H, R 9 , or X,    R 9  is an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, and X is a halogen;                          wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , is a H, R 9 , or X;    R 9  is an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, and X is a halogen; and    combinations thereof;    positioning the inner layer between two planar glass plates, each plate is separated from the other plate so there is a cavity between each plate and the inner layer;    inserting a third polymerizable acrylic material into the cavity;    heating the inner layer and the third polymerizable acrylic material to form a holographic recording medium having a concentration distribution of the dye.    
     
     
         24 . The method of  claim 23  wherein the at least two distinctive polymerizable acrylic materials and the third polymerizable acrylic material are selected from the group consisting of:  
       
         
           
           
               
               
           
         
         wherein R′=H; or an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R=an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms;  
         .R 2 ″—O—R—O—R 1 ″.  
         wherein R=an alkyl group having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms, R 1 ″ and R 2 ″=—OC (═O)C(R 3 )═CH 2  or H, wherein R 3 =H, an alkyl group, having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms;  
         
           
             
             
                 
                 
             
           
         
         wherein R=a tri- or tetra-substituted aryl group; or a carbon atom;  
         R′=H, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms, R 1 , R 2 , and R 3 =—OC(═O)C(R 4 )═CH 2  or H wherein R 4 =H, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 4 to 20 carbon atoms; and  
         
           
             
             
                 
                 
             
           
         
         wherein R=a tri- or tetra-substituted aryl group; or a carbon atom;  
         R′=H, an alkyl group having 1 to 8 carbon atoms;  
         or an aryl group having 4 to 20 carbon atoms, R 1 ′=R 2 ′=R 3 ′=—CH 2 CH 2 — or —CH 2 CH 2 CH 2 —, R 4 ′=R 5 ′=R 6 ′=—OC(═O)C(R 7 ′)═CH 2  or H wherein R 7 ′=H; or an alkyl having 1 to 8 carbon atoms; or an aryl group having 4 to 20 carbon atoms.  
       
     
     
         25 . The method of  claim 23  wherein the dye is 2-methyl-9,10-phenanthrenequinone.  
     
     
         26 . The method of  claim 23  wherein the dye is 9,10-phenanthrenequinone.  
     
     
         27 . The method of  claim 23  wherein the dye is 4H-cyclopenta[def]phenanthrene-8,9-dione.  
     
     
         28 . The method of  claim 23  wherein the dye is 4,4-dimethylcyclopenta[def]phenanthrene-8,9-dione.  
     
     
         29 . The method of  claim 23  wherein the dye comprises of 75 to 95 weight percent of 9,10-phenanthrenequinone and 25 to 5 weight percent of 9-iodophenanthrene.  
     
     
         30 . The method of  claim 23  wherein the dye is selected from the group consisting of 2-methyl-9,10-phenanthrenequinone, 9,10-phenanthrenequinone, 4H-cyclopenta[def]phenanthrene-8,9-dione, 4,4-dimethylcyclopenta[def]phenanthrene-8,9-dione, and combinations thereof.  
     
     
         31 . The method of  claim 23  wherein the ratio between each distinctive polymerizable acrylic material ranges from 1:99 to 99:1 percent by weight.  
     
     
         32 . The method of  claim 23  wherein the polymerization temperature ranges from 60° C. to 170° C.  
     
     
         33 . The method of  claim 23  wherein the dye is 0.2 to 5 weight percent of the monomer.