Incorporation of markings in optical media

• US 20040121268A1
• Filed: 11/05/2003
• Published: 06/24/2004
• Est. Priority Date: 06/06/2001
• Status: Active Grant

• Current Assignee: Spectra Systems Corporation
• Original Assignee: Spectra Systems Corporation
• Inventors: Lawandy, Nabil M., Conroy, Jeffrey L., Pizzuti, Thomas, Lewis, Dana, Afzal, Robert S., Berube, Allison, Smuk, Andrei
• Granted Patent: US 7,393,623 B2
• Time in Patent Office: Days
• US Class Current: 430/321
• CPC Class Codes: G11B 7/24094 Indication parts or information parts for identification
• CPC Class Codes: G11B 7/252 of layers other than recording layers

Abstract

Optical media having markings that are non-interfering, or substantially non-interfering with readout of data from the optical media are disclosed. The optical media make use of certain formulations of color forming coatings described herein. Protective coatings used to enhance the color forming coatings are also presented. Methods for incorporating the coatings into the optical media are included. In preferred embodiments, the marking is formed in a photosensitive coating that is applied to the optical media, and then cured with a first light. A second light, having a substantially separate band of wavelengths from the first light, is used to image a marking into the coating. The coating is robust to many external influences, such as ambient environmental conditions, and physical wear.

Claims

1. An optical media having at least one layer comprising a formulation comprised of at least one set of photosensitive color forming materials, wherein the at least one set of photosensitive color forming materials is adapted for forming at least one marking upon exposure to a source of marking light;

wherein, upon formation, the at least one marking is apparent in at least a readout area of the optical media and is substantially non-interfering with a readout light for the optical media.

2. The optical media as in claim 1, wherein the layer comprises at least one of a substrate layer, a bonding layer and a protective layer.

3. The optical media as in claim 1, wherein the format of the optical media comprises at least one of a substrate layer, a bonding layer, a semi-reflective layer, a reflective layer, and a protective layer.

4. The optical media as in claim 1, wherein the at least one set of photosensitive color forming materials is sensitive to a second set of wavelengths for forming the marking, the second set of wavelengths substantially separate from a first set of wavelengths used for curing the formulation.

5. The optical media as in claim 4, wherein the first set of wavelengths comprises wavelengths above about 370 nm.

6. The optical media as in claim 4, wherein the second set of wavelengths comprises wavelengths in the range of between about 270 nm and about 320 nm.

7. The optical media as in claim 1, wherein the formulation comprises a mixture of a photoacid generator, a color former and a base material.

8. The optical media as in claim 7, wherein the photoacid generator comprises at least one of:

bis (4-tert-butylphenyl) iodonium p-toluenesulfonate;

(tert-butoxycarbonylmethoxynaphthyl) diphenyl sulfonium triflate;

(4-phenoxyphenyl) diphenyl sulfonium triflate;

(4-tert-Butylphenyl) diphenyl sulfonium triflate;

diphenyliodonium hexafluorophosphate;

diphenyliodonium triflate;

triphenylsulfonium triflate;

2-methyl-4,6-bis(trichloromethyl)-s-triazine;

tris(2,4,6-trichloromethyl)-s-triazine;

2-phenyl-4,6-bis(trichloromethyl)-s-triazine;

2-(4-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine;

(4-methylphenyl)diphenyl sulfonium triflate; and

, diphenyl iodonium hexafluorophosphate.

9. The optical media as in claim 7, wherein the color former exhibits at least one absorption peak at wavelengths comprising one of about 540 nm;

about 440 nm and about 600 nm;

about 464 nm and about 586 nm;

about 493 nm;

about 440 nm and about 602 nm;

about 613 nm;

about 460 nm and 586 nm; and

, about 525 nm.

10. The optical media as in claim 7, wherein the base material comprises at least one disc molding material.

11. The optical media as in claim 7, wherein the base material comprises at least one acrylate.

12. The optical media as in claim 11, wherein the at least one acrylate comprises at least one of:

ethoxylated pentaerythritol tetraacrylate;

1,6 hexanediol diacrylate;

tetrahydrofurfuryl acrylate;

highly propoxylated (5.5) glyceryl triacrylate;

3 mole propoxylated glyceryl triacrylate;

3 mole ethoxylated trimethylolpropane triacrylate;

tris (2-hydroxy ethyl) isocyanurate triacrylate;

ditrimethylolpropane tetraacrylate;

urethane diacrylate oligomer;

isobomyl acrylate;

a difunctional bisphenol A based epoxy acrylate;

an aliphatic diacrylate oligomer;

tris (2-hydroxy ethyl) isocyanurate triacrylate;

2-phenoxyethyl acrylate;

a difunctional bisphenol A based epoxy acrylate blended with about 40% 1,6 hexanediol diacrylate;

a difunctional bisphenol A based epoxy acrylate blended with about 50%, 2-phenoxyethyl acrylate; and

acrylic acid.

13. The optical media as in claim 11, wherein the at least one acrylate comprises at least one non-alkoxylated monomer.

14. The optical media as in claim 7, wherein the base material comprises at least one photoinitiator.

15. The optical media as in claim 14, wherein the photoinitiator comprises at least one of:

a stable liquid mixture of trimethylbenzoyldiphenylphosphine oxide, a-hydroxyketones, and benzophenone derivatives;

2-Benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1;

Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide;

an eutectic liquid mixture of;

2,4,6 trirnethylbenzophenone and 4 methylbenzophenone;

a mixture of about 50% 2,4,6-Trimethylbenzoyl-diphenyl-phosphineoxide and about 50% 2-Hydroxy-2-methyl-1-phenyl-propan-1-one;

1-[4-(2-Hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one;

isopropyl thioxanthone;

a liquid mixture of about 70% Oligo [2-hydroxy-2-methyl-1-[4-(1-methylvinyl) phenyl] propanone and about 30% 2-hydroxy-2-methyl-1-phenyl propan-1-one.

16. The optical media as in claim 7, wherein the base material comprises a wetting agent.

17. The optical media as in claim 16, wherein the wetting agent comprises at least one of a polyether modified poly-dimethyl-siloxane;

a crosslinkable silicone polyether acrylate; and

a crosslinkable silicone acrylate.

18. The optical media as in claim 16, wherein the formulation comprises the wetting agent in a range of between about 0.3 weight percent and about 1 weight percent.

19. The optical media as in claim 7, wherein the formulation comprises the photoacid generator in a range of between about 1.5 weight percent to about 9 weight percent.

20. The optical media as in claim 7, wherein the formulation comprises the color former in a range of between about 3 weight percent to about 9 weight percent.

21. The optical media as in claim 7, wherein the formulation comprises the base material in a range of between about 82 weight percent to about 95.5 weight percent.

22. The optical media as in claim 7, wherein the base material comprises a photoabsorptive material.

23. The optical media as in claim 7, wherein the base material comprises a color enhancing material.

24. The optical media as in claim 7, wherein the base material comprises about 0.3 weight percent of a polyether modified poly-dimethyl-siloxane;

about 10 weight percent of a stable liquid mixture of trimethylbenzoyldiphenylphosphine oxide, α

-hydroxyketones, and benzophenone derivatives;

about 10 weight percent of a 1,6 hexanediol diacrylate;

about 15 weight percent of tetrahydrofurfiryl acrylate;

about 32.35 weight percent of ethoxylated (4) pentaerythritol tetraacrylate; and

about 32.35 weight percent of a highly propoxylated (5.5) glyceryl triacrylate.

25. An optical media comprising:

a first layer comprised of photosensitive color forming materials for forming a marking in response to illumination with a marking light, and a second layer disposed over the first layer and comprised of a material absorptive of the marking light;

wherein, the marking is apparent in at least a readout area of the optical media and is substantially non-interfering with a readout light for the optical media.

26. The optical media as in claim 25, where the second layer comprises at least one UV photoabsorptive material.

27. The optical media as in claim 26, wherein the at least one UV photoabsorptive material comprises one of:

2,4-di-tert-butyl-6-(5-chlorobenzotria zol-2-yl) phenol;

2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methyl-phenol;

a mixture of reaction products of methyl 3-(3-(2H-benzotraizole-2-yl)-5-t-butyl-4-hydroxyphenyl) proprionate and PEG 300;

branched and linear 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol;

2-(2′

hydroxy-5′

methacryloxyethylphenyl)-2H-benzotriazole;

2,2′

-dihydroxy-4-methoxybenzophenone;

2-Hydroxy-4-n-octoxybenzophenone; and

, octyl methoxycinnamate.

28. The optical media as in claim 26, wherein the second layer comprises the at least one UV photoabsorptive material in a range of between about 5 weight percent and about 20 weight percent.

29. An optical media having at least one layer comprised of at least one set of photosensitive color forming materials, wherein the at least one set of photosensitive color forming materials forms at least one marking in a readout area of the optical media that is substantially non-interfering with a readout light for the optical media.

30. The optical media as in claim 29, wherein the format of the optical media comprises at least one of a substrate layer, a bonding layer, a semi-reflective layer, a reflective layer and a protective layer.

31. The optical media as in claim 29, wherein the at least one marking is formed when the set of photosensitive color forming materials is illuminated with wavelengths comprising at least one of:

UV-A, UV-B, UV-C, wavelengths.

32. The optical media as in claim 29, wherein the marking is exhibited in the collective appearance of a plurality of layers.

33. The optical media as in claim 29, wherein the marking degrades over time.

34. The optical media as in claim 29, wherein the marking comprises at least one of identification information, authentication information, instruction information, encryption information and promotion information.

35. The optical media as in claim 29, wherein the marking comprises at least one of an image, an alphanumeric character, a symbol, a graphic, a datacode symbology and a digital watermark.

36. The optical media as in claim 29, wherein the marking is substantially non-interfering with wavelengths of about 400 nm, about 440 nm, about 630 nm, about 650 nm and about 780 nm.

37. The optical media as in claim 29, further comprising a color enhancing additive.

38. The optical media as in claim 29, wherein the marking comprises at least one of a non-colored marking, a single color marking and a multi-color marking.

39. A method for producing an optical media, comprising:

selecting a formulation comprising at least one set of photosensitive color forming materials, wherein the at least one set of photosensitive color forming materials is adapted for forming at least one marking upon exposure to a source of marking light, wherein the at least one marking, upon formation, appears in at least a readout area of the optical media and is substantially non-interfering with a readout light for the optical media; and

,

applying the formulation in at least a portion of at least one layer of the optical media.

40. The method as in claim 39, wherein applying comprises spincoating the formulation.

41. The method as in claim 39, wherein applying comprises curing the formulation by exposing the formulation to a first light comprising a set of wavelengths substantially separate from the set of wavelengths comprising the marking light.

42. The method as in claim 39, wherein applying comprises forming a mixture by compounding the formulation with a base material and applying the mixture to the optical media.

43. The method as in claim 42, wherein applying the mixture comprises injection molding.

44. The method as in claim 39, further comprising forming an image by exposing the at least a portion of the at least one layer to patterned marking light.

45. The method as in claim 44, wherein exposing comprises one of using a photomask and a direct writing laser.

46. The method as in claim 39, further comprising applying a further layer over at least the portion of the at least one layer, wherein the further layer comprises material absorptive of the marking light.

47. An optical media having at least one first layer comprised of about 0.3 weight percent of a polyether modified poly-dimethyl-siloxane;

about 10 weight percent of a stable liquid mixture of trimethylbenzoyldiphenylphosphine oxide, α

-hydroxyketones, and benzophenone derivatives;

about 10 weight percent of a 1,6 hexanediol diacrylate;

about 15 weight percent of tetrahydrofuryl acrylate;

about 32.35 weight percent of ethoxylated (4) pentaerythritol tetraacrylate;

about 32.35 weight percent of a highly propoxylated (5.5) glyceryl triacrylate;

about 3 weight percent of triphenylsulfonium triflate and a color former having a wavelength absorbance peak of about 540 nm.

48. An optical media as in claim 47, further comprising:

at least one second layer disposed over the at least one first layer and comprising about 10 weight percent of 2,2′

-dihydroxy-4-methoxybenzophenone in a base comprising about 1 weight percent of a crosslinkable silicone polyether acrylate;

about 8 weight percent of a stable liquid mixture of trimethylbenzoyldiphenylphosphine oxide, α

-hydroxyketones, and benzophenone derivatives;

about 26 weight percent of 2-phenoxyethyl acrylate;

about 20 weight percent of tris (2-hydroxy ethyl) isocyanurate triacrylate; and

about 45 weight percent of a difunctional bisphenol A based epoxy acrylate blended with about 50% weight percent of phenoxy ethyl acrylate.

49. An optical media having a protective layer comprising a formulation comprised of at least one set of photosensitive color forming materials, wherein the at least one set of color forming materials is adapted for forming at least one marking upon exposure to a source of marking light;

wherein, upon formation, the at least one marking is apparent in the optical media.

50. An optical media having a bonding layer comprising a formulation comprised of at least one set of photosensitive color forming materials, wherein the at least one set of color forming materials is adapted for forming at least one marking upon exposure to a source of marking light;

wherein, upon formation, the at least one marking is apparent in the optical media.

51. An optical media having a substrate layer comprising a formulation comprised of at least one set of photosensitive color forming materials, wherein the at least one set of color forming materials is adapted for forming at least one marking upon exposure to a source of marking light;

wherein, upon formation, the at least one marking is apparent in the optical media.