Photopolymerizable compositions sensitive to longer wavelength visible actinic radiation

Claim 2

The composition of claim 1 wherein said squarylium sensitizer is selected of the group consisting of: 3H-Indolium, 2-[[3-[(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene) methyl]-2-hydroxy-4 -oxo-2-cyclobuten-1-ylidene]methyl]-1,3,3-trimethyl-, hydroxide, inner salt; 3H-Indolium, 5-chloro-2-[[3-[(5-chloro-1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene]methyl]-1,3,3-trimethyl-, hydroxide, inner salt; 3H-Indolium, 5-methoxy-2-[[3-[(5-methoxy-1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene]methyl]-1,3,3-trimethyl-, hydroxide, inner salt; Benzothiazolium, 3-ethyl-2-[[3-[3-ethyl-2(3H)-benzothiazolylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene]methyl]-, hydroxide, inner salt; 3H-Indolium, 2-[[3-[(4-dimethylamino)phenyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene]-methyl]-1,3,3-trimethyl-, hydroxide, inner salt; and 3H-Indolium, 2-[[2-hydroxy-4-oxo-3-[[1-(2-phenylethyl)-2(1H)-pyridinylidene]methyl]-2-cyclobuten-1-ylidene]methyl]-1,3,3-trimethyl-, hydroxide, inner salt.

Claim 3

The composition of claim 1 wherein the hexaarylbisiimidazole is selected from the group consisting of: 1,1'-biimidazole, 2,2'-bis( o -chlorophenyl)-4,4',5,5'-tetraphenyl-; 2-( o -chlorophenyl)-4,5-bis( m -methoxyphenyl)-imidazole dimer; 1,1'biimidazole, 2,2'-bis[ p -nitrophenyl]-4,4',5,5'-tetraphenyl-; and 1H-imidazole, 2,5-bis( o -chlorophenyl)-4-[3,4-dimethoxyphenyl]-, dimer.

Claim 4

The composition of claim 1 additionally comprising a sensitizer which absorbs in the shorter wavelength region of the visible spectrum.

Claim 5

The composition of claim 1 wherein the composition has the following composition based on the total weight of the composition: photoinitiator system about 0.3% to about 15%; monomer about 80% to about 99%; and other ingredients about 0% to about 5%.

Claim 6

The composition of claim 1 additionally comprising a polymeric binder.

Claim 7

The composition of claim 6 wherein X and Y are each independently S or CR₈R₉.

Claim 8

The composition of claim 7 wherein said binder is solvent soluble and either said monomer or said binder contains a substituent selected from the group consisting of (1) an aromatic moiety selected from the group consisting of (i) substituted or unsubstituted phenyl, (ii) substituted or unsubstituted naphthyl, and (iii) substituted or unsubstituted heterocyclic aromatic moiety having up to three rings; (2) chlorine; (3) bromine and mixtures thereof; and the other constituent is substantially free of said substituent.

Claim 9

The composition of claim 8 wherein said monomer contains said substituent and said binder is substantially free of said substituent.

Claim 10

The composition of claim 7 wherein the composition has the following composition based on the total weight of the composition: binder, 25 to 90%, monomer, 5 to 60%, photoinitiator system, 0.1 to 10%, and other ingredients, 0 to 30%.

Claim 11

The composition of claim 7 wherein R₁ is moiety A; X and Y are identical and equal to C(CH₃)₂; R₂ and R₄ are identical and equal to CH₃ or C₂H₅; and R₃ and R₅ are identical.

Claim 12

The composition of claim 7 wherein R₁₀ is Cl and/or R₁₁ is Cl or NO₂, with the proviso that R₁₁ may be H, CH₃ or OCH₃ when R₁₀ is Cl, and that R₁₀ may be H, Cl or CH₃ when R₁₁ is Cl or NO₂; and, the other positions on the phenyl radicals are either unsubstituted or substituted with Cl, CH₃ or OCH₃.

Claim 13

The composition of claim 11 wherein R₁₀ is Cl and/or R₁₁ is Cl or NO₂, with the proviso that R₁₁ may be H, CH₃ or OCH₃ when R₁₀ is Cl, and that R₁₀ may be H, Cl or CH₃ when R₁₁ is Cl or NO₂; and, the other positions on the phenyl radicals are either unsubstituted or substituted with Cl, CH₃ or OCH₃.

Claim 14

The composition of claim 13 wherein said monomer or monomers contain a substituent selected from the group consisting of (1) an aromatic moiety selected from the group consisting of (i) substituted or unsubstituted phenyl, (ii) substituted or unsubstituted naphthyl, and (iii) substituted or unsubstituted heterocyclic aromatic moiety having up to three rings; (2) chlorine; (3) bromine and mixtures thereof; and said binder is substantially free of said substituent.

Claim 15

The composition of claim 14 wherein said binder is selected from the group consisting of cellulose acetate butyrate, poly(methyl methacrylate), poly(vinyl butyral), poly(vinyl acetate), or copolymers of vinyl acetate with tetrafluoroethylene and/or hexafluoropropylene containing 3 to 25% by weight fluorine, and mixtures thereof.

Claim 16

The composition of claim 15 additionally comprising a sensitizer which absorbs in the shorter wavelength region of the visible spectrum, wherein said sensitizer is cyclopentanone, 2,5-bis[(2,3,6,7-tetrahydro-1H,5H-benzo[i,j]quinolizin-9-yl)methylene]-.

Claim 17

The composition of claim 12 wherein R₂ and R₄ are identical and equal to CH₃; and R₃ and R₅ are identical and equal to H or Cl.

Claim 18

The composition of claim 17 in which R₃ and R₅ are identical and equal to H.

Claim 19

A process for forming a light-stable hologram comprising exposing to modulated actinic radiation comprising an object beam and a reference beam bearing holographic information a photopolymerizable layer comprising: (a) a squarylium sensitizer of the following structure: where R₁ is: or a p -(N,N-dialkylamino)phenyl in which the alkyl groups are from about 1 to about 4 carbon atoms; X and Y are each independently O, S, NR₇, or CR₈R₉ where R₇, R₈, and R₉ are each independently an alkyl group of about 1 to about 6 carbon atoms or substituted or unsubstituted phenyl; R₂ and R₄ are each independently a substituted or unsubstituted alkyl group from about 1 to about 7 carbon atoms; R₃ and R₅ are each independently H, Cl or OCH₃ with the proviso that when X is S, R₃ is H and that when Y is S, R₅ is H; and R₆ is a substituted or unsubstituted alkyl group of from about 1 to about 8 carbon atoms; (b) a hexaarylbisimidazole of the following structure: where R₁₀ is Cl, H or CH₃, and R₁₁ is Cl, NO₂, H, CH₃ or OCH₃ with the proviso that either R₁₀ is Cl or R₁₁ is C1 or NO₂; and, any other position on the three phenyl radicals of (b) is either unsubstituted or substituted with Cl, CH₃ or OCH₃; (c) a solvent soluble, polymeric binder; and (d) at least one ethylenically unsaturated monomer capable of free radical initiated addition polymerization and having a boiling point above 100°C.

Claim 20

The process of claim 19 additonally comprising a second, overall exposure to actinic radiation.

Claim 21

The process of claim 20 wherein the composition has the following composition based on the total weight of the composition: binder 25 to 90%, monomer, 5 to 60%, photoinitiator system 0.1 to 10%, and other ingredients, 0 to 30%.

Claim 22

The process of claim 21 wherein X and Y are each independently S or CR₈R₉.

Claim 23

The process of claim 22 wherein said binder is solvent soluble and either said monomer or said binder contains a substituent selected from the group consisting of (1) an aromatic moiety selected from the group consisting of (i) substituted or unsubstituted phenyl, (ii) substituted or unsubstituted naphthyl, and (iii) substituted or unsubstituted heterocyclic aromatic moiety having up to three rings; (2) chlorine; (3) bromine and mixtures thereof; and the other constituent is substantially free of said substituent.

Claim 24

The process of claim 23 wherein said monomer contains said substituent and said binder is substantially free of said substutuent.

Claim 25

The process of claim 23 wherein R₁ is moiety A; X and Y are identical and equal to C(CH₃)₂; R₂ and R₄ are identical and equal to CH₃ or C₂H₅; and R₃ and R₅ are identical.

Claim 26

The process of claim 23 wherein R₁₀ is Cl and/or R₁₁ is Cl or NO₂, with the proviso that R₁₁ is H, CH₃ or OCH₃ when R₁₀ is Cl, and that R₁₀ is H, Cl or CH₃ when R₁₁ is Cl or NO₂; and, the other positions on the phenyl radicals are either unsubstituted or substituted with Cl, CH₃ or OCH₃.

Claim 27

The process of claim 25 wherein R₁₀ is Cl and/or R₁₁ is Cl or NO₂, with the proviso that R₁₁ is H, CH₃ or OCH₃ when R₁₀ is Cl, and that R₁₀ is H, Cl or CH₃ when R₁₁ is Cl or NO₂; and, the other positions on the phenyl radicals are either unsubstituted or substituted with Cl, CH₃ or OCH₃.

Claim 28

The process of claim 27 wherein said binder is selected from the group consisting of cellulose acetate butyrate, poly(methyl methacrylate), poly(vinyl butyral), poly(vinyl acetate), or copolymers of vinyl acetate with tetrafluoroethylene and/or hexafluoropropylene containing 3 to 25% by weight fluorine, and mixtures thereof.

Claim 29

The procees of claim 27 wherein said photopolymerizable composition additionally comprises a sensitizer which absorbs in the shorter wavelength region of the visible spectrum.

Claim 30

The process of claim 21 wherein said object beam and said reference beam are incident on opposite sides of said photopolymerizable layer.

Claim 31

The process of claim 30 additionally comprising the step of heating said photopolymerizable composition to 100-150°C for about 0.5-1.5 hr following said second, overall exposure.