Polarizer film
Assignee3M Innovative Properties Company
InventorsCarl A. Stover, Kristopher J. Derks, Stephen A. Johnson, Benjamin J. Forsythe
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Abstract
Multi-layer optical films that can be utilized as polarizer or mirror films and can be incorporated into optical stacks. The optical film includes a plurality of alternating polymeric first and second interference layers numbering greater than 50 and disposed between, and integrally formed with, first and second skin layers, each of the first and second interference layers has an average thickness less than 250 nm. The first and second interference layers and the first and second skin layers are compositions that include polyester.
Claims20
An optical film, comprising:
- a plurality of alternating first and second polymeric layers numbering greater than 50 and disposed between, and integrally formed with, first and second skin layers, an index of refraction of the first polymeric layers being greater than an index of refraction of the second polymeric layers for at least one in-plane direction and for at least one wavelength in a predetermined wavelength range extending at least from about 430 nm to at least about 600 nm,
- wherein:
- the second skin layer comprises at least 70% by weight of polyethylene terephthalate;
- the first polymeric layers comprise a polyester comprising diol moieties and diacid moieties, the diol moieties comprising about 20-60 mole % cyclohexane dimethanol and about 40-80 mole % ethylene glycol, the diacid moieties comprising greater than 75 mole % naphthalene dicarboxylate;
- and
- for substantially normally incident light and for each wavelength in the predetermined wavelength range, the optical film has an optical reflectance of at least 50% for a first polarization state.
An optical film comprising a plurality of alternating polymeric first and second polymeric layers numbering greater than 50 and disposed between, and integrally formed with, first and second skin layers, the first polymeric layers comprising polyester comprising diacid moieties comprising naphthalene dicarboxylate,
- the second skin layer comprising at least 70% by weight of polyethylene terephthalate (PET),
- wherein for substantially normally incident light and for each wavelength in a predetermined wavelength range extending at least from about 400 nm to about 600 nm, the optical film has an optical reflectance of at least 50% for a first polarization state, and
- wherein the first and second skin layers, in combination, comprise at least 70% by volume of polyester.
Dependencies are inferred from the claim text.