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EP-4741470-A1 - POLYMERISABLE LC MATERIAL AND POLYMER FILM

EP4741470A1EP 4741470 A1EP4741470 A1EP 4741470A1EP-4741470-A1

Abstract

The instant invention relates to an optical component and a electro optical devices comprising the optical component. The instant invention further relates to a cholesteric polymerizable liquid crystalline (LC) material preferably utilized in an optical component in accordance with the present invention, to a process for the production of the cholesteric polymerizable LC material, to a process to convert the cholesteric polymerizable material into a polymer film, a polymer film obtainable from the cholesteric polymerizable LC material, the use of the polymer films in an optical component or device comprising a polymer film in accordance with the invention.

Inventors

  • MULCAHY, STEPHEN
  • PARRI, OWAIN LLYR

Assignees

  • Merck Patent GmbH

Dates

Publication Date
20260513
Application Date
20211117

Claims (12)

  1. Cholesteric polymerizable LC material comprising one or more compounds selected from formulae A and B, wherein P is a polymerizable group, Sp is a spacer group or a single bond, R 11 is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy, preferably with 1 to 15 C atoms which is optionally fluorinated. A denotes, an aromatic or alicyclic group, which optionally containing one or more heteroatoms selected from N, O and S, and optionally mono- or polysubstituted by L, L is F, Cl, Br, I, -CN, -NO 2 , -NCO, -NCS, -OCN, -SCN, -C(=O)NR x R y , -C(=O)OR x , -C(=O)R × , -NR x R y , -OH, -SF 5 , or straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12 C atoms, wherein one or more H atoms are optionally replaced by F or Cl, preferably F, -CN or straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 6 C atoms, R 00 , R 000 , R x and R y independently of each other denote H or alkyl with 1 to 12 C-atoms, Z 11 and Z 12 denotes, in case of multiple occurrence independently of one another, -O-, -S-, -CO-, -COO-, -OCO-, -S-CO-, -CO-S-, -O-COO-, -CO-NR 00 -, -NR 00 -CO-, -NR 00 -CO-NR 000 , -NR 00 -CO-O-, -O-CO-NR 00 -, -OCH 2 -, -CH 2 O-, -SCH 2 -, -CH 2 S-, -CF 2 O-, -OCF 2 -, -CF 2 S-, -SCF 2 -, -CH 2 CH 2 -, -(CH 2 ) n1 , -CF 2 CH 2 -, -CH 2 CF 2 -, -CF 2 CF 2 -, -CH=N-, -N=CH-, -N=N-, -CH=CR 00 -, -CY 1 =CY 2 -, -C≡C-, -CH=CH-COO-, -OCO-CH=CH- or a single bond, preferably -COO-, -OCO- or a single bond, more preferably -COO- or -OCO-, Y 1 and Y 2 independently of each other denote H, F, Cl or CN, and n1 is an integer from 1 to 10, preferably 1, 2, 3 or 4, L a is, in case of multiple occurrence identically or differently F, Cl, CN, SCN, SF 5 or straight-chain or branched, optionally mono- or polyfluorinated alkyl, alkoxy, alkenyl, alkynyl, alkylcarbonyl, alkoxycarbonyl, or alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms, (wherein the groups different from alkyl and alkoxy contain at least 2 C atoms and branched groups contain at least 3 C atoms) or optionally halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms, r is 0, 1, 2, 3 or 4.
  2. Cholesteric polymerizable LC material according to claim 1, characterized in that in the compounds of formula A denotes a radical selected from the following groups: a) a group consisting of 1,4-phenylene and 1,3-phenylene, wherein, in addition, one or two CH groups may be replaced by N and wherein, in addition, one or more H atoms may be replaced by L, b) a group selected from the group consisting of where, in addition, one or more H atoms in these radicals may be replaced by L, and/or one or more double bonds may be replaced by single bonds, and/or one or more CH groups may be replaced by N, c) a group consisting of trans-1,4-cyclohexylene, 1,4-cyclo-hexenylene, wherein, in addition, one or more non-adjacent CH 2 groups may be replaced by -O- and/or -S- and wherein, in addition, one or more H atoms may be replaced by F, or d) a group consisting of tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, tetrahydrofuran-2,5-diyl, cyclobutane-1,3-diyl, piperidine-1,4-diyl, thiophene-2,5-diyl and selenophene-2,5-diyl, each of which may also be mono- or polysubstituted by L, and wherein L on each occurrence, identically or differently, denotes -OH, -F, -Cl, -Br, -I, -CN, -NO 2 , SF 5 , -NCO, -NCS, -OCN, -SCN, -C(=O)N(R z ) 2 , -C(=O)R z , -N(R Z ) 2 , optionally substituted silyl, optionally substituted aryl having 6 to 20 C atoms, or straight-chain or branched or cyclic alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, preferably 1 to 12 C atoms, more preferably 1 to 6 C atoms , in which, in addition, one or more H atoms may be replaced by F or Cl.
  3. Cholesteric polymerizable LC material according to claim 1 or 2, characterized in that in the compounds of formula A denotes a radical selected from a group consisting of 1,4-phenylene, wherein, in addition, one or two CH groups may be replaced by N and wherein, in addition, one or more H atoms may be replaced by L, wherein L on each occurrence, identically or differently, denotes -OH, -F, -Cl, or straight-chain, branched or cyclic alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, preferably 1 to 12 C atoms, more preferably 1 to 6 C atoms , in which, in addition, one or more H atoms may be replaced by F or Cl.
  4. Cholesteric polymerizable LC material according to one or more of claims 1 to 3, characterized in that the compounds of formula B are selected from the following subformula: wherein P a independently of one another has one of the meanings given in claim 1 and x, y, z, are independently of each other 0 or identical or different integers from 1 to 12.
  5. Cholesteric polymerizable LC material according to claim 4, characterized in that P 2 is independently of one another an acryl, methacryl, oxetane, 3-ethyloxetane, epoxy, vinyloxy or styrene group.
  6. Cholesteric polymerizable LC material according to one or more of claims 1 to 5, characterized in that it comprises one or more compounds of formula A and one or more compounds of formula B.
  7. Cholesteric polymerizable LC material according to one or more of claims 1 to 6, comprising one or more mono-or direactive chiral compounds selected from compounds of formula CRMa to CRMc: wherein P 0* denotes a polymerizable group P Sp* denotes a spacer Sp A 0 and B 0 are, in case of multiple occurrence independently of one another, 1,4-phenylene that is unsubstituted or substituted with 1, 2, 3 or 4 groups L as defined above, or trans-1,4-cyclohexylene, X 1 and X 2 are independently of each other -O-, -COO-, -OCO-, -O-CO-O- or a single bond, Z 0* is, in case of multiple occurrence independently of one another, -COO-, -OCO-, -O-CO-O-, -OCH 2 -, -CH 2 O-, -CF 2 O-, -OCF 2 -, -CH 2 CH 2 -, -(CH 2 ) 4 -, -CF 2 CH 2 -, -CH 2 CF 2 -, -CF 2 CF 2 -, -C≡C-, -CH=CH-, -CH=CH-COO-, -OCO-CH=CH- or a single bond, t is, independently of each other 0, 1, 2 or 3, a is 0, 1 or 2, b is 0 or an integer from 1 to 12, z is 0 or 1, and wherein the naphthalene rings in formula CRMa can additionally be substituted with one or more identical or different groups L, wherein L is, independently of each other F, Cl, CN, halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms.
  8. Process for the preparation of the cholesteric polymerizable LC material according to one or more of claims 1 to 7, comprising the steps of mixing one or more compounds of formula A and/or B, with one or more chiral compounds.
  9. Process for the conversion of the cholesteric polymerizable LC material according to one or more of claims 1 to 7, into a cholesteric polymer film comprising the steps of providing a layer of a cholesteric polymerizable LC material according to one or more of claims 1 to 7 onto a substrate, polymerizing the cholesteric polymerizable LC material by photopolymerization, and optionally removing the polymer film from the substrate and/or optionally providing it onto another substrate.
  10. Polymer film obtainable from a cholesteric polymerizable LC material according to one or more of claims 1 to 7.
  11. Use of a polymer film according to claim 10 and/or a cholesteric polymerizable LC material according to one or more of claims 1 to 7 in an optical component or electrooptical device.
  12. Optical component or electrooptical device comprising a polymer film according to claim 10 and/or a cholesteric polymerizable LC material according to one or more of claims 1 to 7.

Description

Technical Field The instant invention relates to an optical component and electro optical devices comprising the optical component. The instant invention further relates to a cholesteric polymerizable liquid crystalline (LC) material preferably utilized in an optical component in accordance with the present invention, to a process for the production of the cholesteric polymerizable LC material, to a process to convert the cholesteric polymerizable material into a polymer film, a polymer film obtainable from the cholesteric polymerizable LC material, the use of the polymer films in an optical component or device comprising a polymer film in accordance with the invention. Background and Prior Art Organic light emitting diode (OLED) displays require a circular polarizer in the display stack to reduce reflections of external light and increase the ambient contrast ratio. This is because the electrodes in an OLED display are reflective and without the utilization of a circular polarizer, the ambient light reflecting off the electrodes will make it hard to see the image being displayed. The disadvantage of using a circular polarizer for this application is that ~50% of emitted light is blocked from leaving the display by the circular polarizer. This large loss in efficiency can lead to the utilization of more than one emissive layer per colour as well as increased power consumption to make up for the loss in brightness. For instance US 2005/035353 A1 discloses light emitting displays which produce a bright image by efficiently emitting light radiated from a light-emitting thin-film layer to the viewer side, and also produces a high-quality image of high contrast ratio and changing in color to a limited extent over a wide viewing angle range even in a bright atmosphere. The light emitting displays are provided with a plurality of light-emitting devices, each device having a light-emitting thin-film layer and a light reflective surface in this order on the back side, and a circularly polarized light reflective layer which separates incident light into two types of circularly polarized components, one being reflected and the other transmitted by the reflective layer, an optical compensation layer, a quarter-wave plate and a polarizer on the front side, wherein the optical compensation layer is composed of a transparent body working as an optical indicatrix having little refractive index distribution in the in-plane direction and having a refractive index in the thickness direction different from that in the in-plane direction. US 2018/006274 A1 discloses an optical member for enhancing luminance and an organic light-emitting display device having the same. An optical member includes: a linear polarizer, a blue cholesteric liquid crystal (CLC) layer configured to transmit light, the light having only one of: a left-handed circularly polarized light component and a right-handed circularly polarized light component, and a quarter wave plate configured to convert the transmitted light, having the left-handed circularly polarized light component or right-handed circularly polarized light component, into linear polarized light, wherein the blue cholesteric liquid crystal (CLC) layer and the quarter wave plate are located on a same side of the linear polarizer. US 2011/134020 A1 discloses an organic light emitting diode display is disclosed. The display includes a first semitransparent electrode, an organic emissive layer placed on the first semitransparent electrode, a second semitransparent electrode placed on the organic emissive layer, and a first selective reflection layer placed on the second semitransparent electrode. EP 1514316 A1 discloses An electroluminescent device, such as a light emitting diode, which has a light-reflecting surface causing undesirable reflection of ambient light incident on the device is provided with a combination of a reflective circular polarizer and an absorbing circular polarizer to suppress the undesirable reflection of ambient light thus improving the contrast of the device when used under high intensity ambient lighting conditions while maintaining a satisfactory brightness. The reflection band of the reflective circular polarizer regions of the reflective circular polarizer are preferably tuned to the corresponding emission band of the luminescent regions of the electroluminescent device to further increase the contrast of the device while substantially maintaining the same brightness. The above-mentioned approaches are effective for each emissive pixel; however, an OLED is typically pixelated into three (or sometimes more) pixels and only parts of the surface area contain a blue emitter. Although the blue reflecting layer helps to increase the transmission of the blue, it also increases the reflectance because both the left-handed and right-handed portion of the external ambient unpolarised light are able to be reflected from the OLED emitter surface in such a way that it is transmi