Polymerizable liquid crystal material and polymerized liquid crystal film

Abstract

A polymerizable LC material comprising one or more reactive mesogenic compounds, one or more chiral compounds and a block copolymer that comprises at least one polyfluorooxetane block bonded to a polyether block, said polyfluorooxetane block having a repeating unit of the formula ##STR00001## Further, a method for its preparation, a polymer film obtainable from a corresponding polymerizable LC material, a method of preparation of such polymer film, and the use of such polymer film and said polymerizable LC material in optical, electro-optical, decorative or security devices.

Claims

1. A polymerizable LC material, comprising one or more reactive mesogenic compounds, one or more chiral compounds, and a block copolymer that comprises at least one polyfluorooxetane block bonded to a polyether block, wherein said polyfluorooxetane block has one or more repeating units of the formula ##STR00108## wherein each n and m are each and independently an integer from 1 to 6, R is hydrogen or an alkyl group having from 1 to 6 carbon atoms, R.sub.f and R.sub.f* are each and independently a linear or branched alkyl group of from 1 to 20 carbon atoms with a minimum of 50% of the hydrogen atoms of said R.sub.f or R.sub.f* alkyl group being replaced by F, and optionally up to all of the remaining H atoms of said R.sub.f or R.sub.f* alkyl group being replaced by I, Cl, or Br, DP is from 2 to 100.

2. The polymerizable LC material according to claim 1, having a concentration of the block copolymer of from 0.01% to 1%.

3. The polymerizable LC material according to claim 1, comprising one or more reactive mesogens of formula RMT, ##STR00109## wherein P is a polymerizable group, Sp is a spacer group or a single bond, r2 and r3 are independently of each other 0, 1, 2, 3 or 4, R.sup.11 is P-Sp-, alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy that is optionally fluorinated, A and B denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L, wherein one or two non-adjacent CH.sub.2 groups are optionally replaced by O and/or S, wherein A and B are unsubstituted or substituted by 1, 2, 3 or 4 groups L L is P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)OR.sup.x, —C(═O)R.sup.x, —NR.sup.xR.sup.y, —OH, —SF.sub.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, Cl, —CN, or straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 6 C atoms, R.sup.x and R.sup.y independently of each other denote H or alkyl with 1 to 12 C-atoms, Z.sup.11 and Z.sup.12 denotes, in case of multiple occurrence independently of one another, —O—, —S—, —CO—, —COO—, —OCO—, —S—CO—, —CO—S—, —O—COO—, —CO—NR.sup.00—, —NR.sup.00—CO—, —NR.sup.00—CO—NR.sup.000°, —NR.sup.00—CO—O—, —O—CO—NR.sup.00—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —CH.sub.2CH.sub.2—, —(CH.sub.2).sub.n1, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.2—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.00—, —CY.sup.1═CY.sup.2—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond, Y.sup.1 and Y.sup.2 independently of each other denote H, F, Cl or CN, n is 1, 2, 3 or 4, m is 0, 1, 2, 3 or 4, and n1 is an integer from 1 to 10.

4. The polymerizable LC material according to claim 3, having a concentration of compounds of formula RMT of from 40% to 99%.

5. The polymerizable LC material according to claim 1, comprising one or more compounds of formula DRM,
P.sup.1—Sp.sup.1-MG-Sp.sup.2-P.sup.2  DRM wherein P.sup.1 and P.sup.2 independently of each other denote a polymerizable group, Sp.sup.1 and Sp.sup.2 independently of each other are a spacer group or a single bond, and MG is a rod-shaped mesogenic group, wherein compounds of formula RMT are excluded from the compounds of formula DRM.

6. The polymerizable LC material according to claim 5, having a concentration of one or more compounds of formula DRM of from 1% to 60%.

7. The polymerizable LC material according to claim 1, comprising one or more compounds of formula MRM:
P.sup.1-Sp.sup.1-MG-R  MRM wherein P.sup.1 denotes a polymerizable group, Sp.sup.1 is a spacer group or a single bond, and MG is a rod-shaped mesogenic group, R denotes P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)X, —C(═O)OR.sup.x, —C(═O)R.sup.y, —NR.sup.xR.sup.y, —OH, —SF.sub.5, optionally substituted silyl, 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, X is halogen, and R.sup.x and R.sup.y are independently of each other H or alkyl with 1 to 12 C atoms, wherein compounds of formula RMT are excluded from the compound of formula MRM.

8. The polymerizable LC material according to claim 1, wherein the one or more reactive chiral compounds comprise mono-reactive chiral compounds selected from compounds of formula CRMa to CRMc, ##STR00110## wherein P.sup.0* denotes a polymerizable group P Sp* denotes a spacer Sp A.sup.0 and B.sup.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.sup.1 and X.sup.2 are independently of each other —O—, —COO—, —OCO—, —O—CO—O— or a single bond, Z.sup.0* is, in case of multiple occurrence independently of one another, —COO—, —OCO—, —O—CO—O—, —OCH.sub.2—, —CH.sub.2O—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2CH.sub.2—, —(CH.sub.2).sub.4—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.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.

9. The polymerizable LC material according to claim 1, having a concentration of chiral compounds in the liquid-crystalline medium of from 1 to 20%.

10. The polymerizable LC material according to claim 1, comprising one or more additives selected from the group consisting of surfactants, photo initiators, stabilisers, catalysts, sensitizers, inhibitors, chain-transfer agents, co-reacting monomers, reactive thinners, surface-active compounds, lubricating agents, wetting agents, dispersing agents, hydrophobing agents, adhesive agents, flow improvers, degassing or defoaming agents, deaerators, diluents, reactive diluents, auxiliaries, colourants, dyes, pigments and nanoparticles.

11. A process for the preparation of a polymerizable LC material, comprising the steps of mixing one or more block copolymers comprising at least one polyfluorooxetane block bonded to a polyether block, wherein said polyfluorooxetane block has one or more repeating units of the formula ##STR00111## wherein each n and m are each and independently an integer from 1 to 6, R is hydrogen or an alkyl group having from 1 to 6 carbon atoms, R.sub.f and R.sub.f* are each and independently a linear or branched alkyl group of from 1 to about 20 carbon atoms with a minimum of 50% of the hydrogen atoms of said R.sub.f or R.sub.f* alkyl group being replaced by F, and optionally up to all of the remaining H atoms of said R.sub.f or R.sub.f* alkyl group being replaced by I, Cl, or Br, and DP is from 2 to about 100, with one or more reactive mesogenic compounds and one or more chiral compounds.

12. A process for the preparation of the of a polymer film, comprising the steps of: providing a layer of a polymerizable LC material according to claim 1 onto a substrate, photopolymerizing the polymerizable LC material, and optionally removing the polymerized LC material from the substrate and/or optionally providing it onto another substrate.

13. A polymer film obtainable from a polymerizable LC material by a process comprising the steps of: providing a layer of a polymerizable LC material according to claim 1 onto a substrate, photopolymerizing the LC material, and optionally, removing the polymerized LC material from the substrate and/or optionally providing it onto another substrate.

14. An optical component comprising the polymer film according to claim 13.

15. An optical component comprising the polymerizable LC material according to claim 1.

16. An electro optical device comprising the optical component according to claim 14.

17. An electro optical device comprising the polymer film according to claim 13.

18. An electro optical device comprising the polymerizable LC material according to claim 1.

19. The polymerizable LC material according to claim 3, wherein R.sup.11 is P-Sp-, alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 15 C atoms, A and B denote, in case of multiple occurrence independently of one another, 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, thiophene-2,5-diyl, naphthalene-2,6-diyl, 1,2,3,4-tetrahydro-naphthalene-2,6-diyl, indane-2,5-diyl, bicyclooctylene, or 1,4-cyclohexylene, Z.sup.11 and Z.sup.12 denotes, in case of multiple occurrence independently of one another, —COO—, —OCO—, —C≡C—, or a single bond, n is 1 or 2, and m is 0 or 1.

20. The polymerizable LC material according to claim 5, wherein MG is a rod-shaped mesogenic group of formula MG
-(A.sup.1-Z.sup.1).sub.n-A.sup.2-  MG wherein A.sup.1 and A.sup.2 denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L, L is P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)OR.sup.x, —C(═O)R.sup.x, —NR.sup.xR.sup.y, —OH, —SF.sub.5, optionally substituted silyl, aryl or heteroaryl with 1 to 12 C atoms, and 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, R.sup.x and R.sup.y independently of each other denote H or alkyl with 1 to 12 C atoms, Z.sup.1 denotes, in case of multiple occurrence independently of one another, —O—, —S—, —CO—, —COO—, —OCO—, —S—CO—, —CO—S—, —O—COO—, —CO—NR.sup.x—, —NR.sup.x—CO—, —NR.sup.x—CO—NR.sup.y, —NR.sup.x—CO—O—, —O—CO—NR.sup.x—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —(CH.sub.2).sub.n1, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.2—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.x—, —CY.sup.1═CY.sup.2—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond, Y.sup.1 and Y.sup.2 independently of each other denote H, F, Cl or CN, n is 1, 2, 3 or 4, and n1 is an integer from 1 to 10.

21. The polymerizable LC material of claim 7, wherein MG is a rod-shaped mesogenic group of formula MG
-(A.sup.1-Z.sup.1).sub.n-A.sup.2-  MG wherein A.sup.1 and A.sup.2 denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L, L is P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)OR.sup.x, —C(═O)R.sup.x, —NR.sup.xR.sup.y, —OH, —SF.sub.5, optionally substituted silyl, aryl or heteroaryl with 1 to 12 C atoms, and 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, R.sup.x and R.sup.y independently of each other denote H or alkyl with 1 to 12 C atoms, Z.sup.1 denotes, in case of multiple occurrence independently of one another, —O—, —S—, —CO—, —COO—, —OCO—, —S—CO—, —CO—S—, —O—COO—, —CO—NR.sup.x—, —NR.sup.x—CO—, —NR.sup.x—CO—NR.sup.y, —NR.sup.x—CO—O—, —O—CO—NR.sup.x—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —(CH.sub.2).sub.n1, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.2—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.x—, —CY.sup.1═CY.sup.2—, —C═C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond, Y.sup.1 and Y.sup.2 independently of each other denote H, F, Cl or CN, n is 1, 2, 3 or 4, and n1 is an integer from 1 to 10.

Description

DETAILED DESCRIPTION

(1) Preferred are block copolymers wherein said DP is in the range from at least 2 as to about 100 or 200, more preferably from 2 to about 10 or 20, or 30, even more preferably 2 to 6.

(2) Preferred are block copolymers, wherein said polyfluorooxetane block is an oligomer, a polymer, or a copolymer.

(3) Further preferred are block copolymers, wherein total amount of fluorine atoms in each R.sub.f or R.sub.f* group is generally at least 10% or 25%, desirably at least 50% or 75%, and preferably at least 80%, 85%, 90%, or 95%, or even 100% (perfluorinated) of the non-carbon atoms such as trifluoro methyl, pentafluoro ethyl, heptafluoro propyl, etc and of with any remaining non-carbon atoms or nonfluorine atoms being H, or I, or Cl or Br.

(4) The pendant or side chain groups R.sub.f or R.sub.f* can be present on all the monomers comprising the polymer or on a selected few with a preferable range of about 50 to 100% of monomers comprising the polymer containing a pendant or side chain groups R.sub.f or R.sub.f*.

(5) A preferred polymer contains one R.sub.f group and no group R.sub.f* per repeat unit. Therefore, the following repeat unit is preferred

(6) ##STR00014##

(7) Preferably n denotes an integer from 1 to 6, preferably 1, 2, 3 or 4.

(8) R.sub.f denotes independently on each monomer a linear or branched, unsaturated, or preferably saturated alkyl group of 1 to about 7, or about 10, or about 15, or about 20 carbon atoms with a minimum of 25, 50, 75, 80, 85, 90 or 95, or preferably perfluorinated i.e. 100 percent of the H atoms of said R.sub.f being replaced by F, and optionally up to all of the remaining H atoms being replaced by I, Cl or Br.

(9) When R.sub.f is a short chain, it preferably contains 1, 2, 3, or 4 carbon atoms. R.sub.f can either contain a linear alkyl group or a branched alkyl group, preferably a linear alkyl group.

(10) When it is a branched group, the main chain contains from 1 to 7 carbon atoms and each branch chain can contain up to 3 carbon atoms as well.

(11) R is hydrogen, or an alkyl from 1 to 6 carbon atoms with methyl or ethyl being preferred, more preferably methyl.

(12) Suitable polyethers include hydroxyl terminated polyethylene glycol, polypropylene glycol, polybutylene glycol, polyisobutylene glycol, and the like as well as monohydroxyl compounds thereof such as polyethylene glycol methyl ether, polytetrahydrofuran, and the like. Preferably the polyether is neopentyl glycol.

(13) The average molecular weight of such polyethers is generally from about 50 to about 10,000, desirably from about 75 to about 5,000 and preferably from about 100 to about 2,500 and can thus be an monomer, oligomer, polymer or copolymer.

(14) Preferably the block copolymer is an AB, or a BAB, or a BA, or an ABA block copolymer, wherein said A block is said polyether block and said B block is said polyfluorooxetane block.

(15) Block copolymers of polyfluorooxetanes and polyethers can be prepared according to two different routes. In one route, a polyether serves as an initiator which is reacted with fluorooxetane monomers; or alternatively, fluorooxetane oligomers, polymers, or copolymers serve as an initiator which is reacted with alkylene oxide monomers, in the presence of a catalyst to form polyfluorooxetane blocks which are bonded or connected to the polyether, or alternatively to form polyether blocks which are connected to the fluorooxetane oligomer, polymer, or copolymer.

(16) The polyether which serves as an initiator can be made in a manner known to the literature as well as to the art. One common source are alkylene oxide monomers containing from 2 to about 6 carbon atoms and preferably from 2 to about 4 carbon atoms.

(17) The fluorooxetane monomers are those as set forth in 2003/0109662 A1, which is hereby fully incorporated by reference.

(18) Polymerization of the one or more fluorooxetane monomers which is initiated by the one or more polyether functional groups such as a hydroxyl is desirably carried out via solution polymerization and thus is polymerized in the presence of a solvent. Suitable solvents are generally polar and/or halogenated hydrocarbons having a total from 1 to about 6 carbon atoms such as methylene chloride, carbon tetrachloride, chloroform, trichloroethylene, chlorobenzene, ethyl bromide, dichloroethane, and the like, with methylene chloride being preferred.

(19) The amount of such solvents is generally from about 50 to about 100 and desirably from about 50 to about 65 parts by weight for every 100 parts by weight of the polyether initiator and the total weight of the one or more fluorooxetane monomers.

(20) The one or more fluorooxetane monomers which are polymerized onto the polyether initiator having 1 or more functional groups such as a hydroxyl readily polymerize in the presence of the Lewis acid catalyst (ire. compounds capable of accepting a pair of electrons). Such suitable Lewis acids include complexes of boron trifluoride, for example BF.sub.3 etherate, BF.sub.3-THF, antimony pentafluoride, zinc chloride, aluminum bromide, and the like with BF.sub.3-THF being preferred. When BF.sub.3-THF is utilized, the THF will be polymerized and hence a fluorooxetane-THF copolymer will be produced. Generally the amount of THF within the copolymer is from about 0.05 to about 10 or about 12 or about 30 or about 50 percent by weight and desirably from about 0.1 to about 5 percent by weight based upon the total weight of the copolymer.

(21) Polymerization is carried out at temperatures of from about 15° C. to 1 or 2 degrees below the boiling point of the solvent, desirably from about 25° C. to about 45° C., and preferably from about 35° C. to about 40° C. Polymerization times can vary with regard to the temperature and other factors and generally range from about 1% to about 5 hours. Once the various fluorooxetane monomers have been polymerized onto the polyether, the end product which is a block copolymer can be washed with water to remove the solvent.

(22) If the polyether initiator has one functional end group such as a hydroxyl, an AB block copolymer will be formed wherein the B block is derived from the fluorooxetane monomers and the A block is derived from the monohydroxyl polyether. Alternatively, if the polyether has two functional end groups, a BAB block copolymer will be formed. In either situation, the B block will have a hydroxyl end group.

(23) Including a block copolymer as described above and below in a polymerizable LC material allows easy formation of an aligned CLC phase with no visible haze while also allowing another layer to be coated on top which gives good alignment without the need for a second alignment layer.

(24) Choosing this block copolymer type also does not have any problems with dewetting of the upper layer in a layer stack, which is common when using surfactant additives.

(25) The concentration of block copolymers as described above and below in the polymerizable LC material is preferably from 0.01% to 1%, more preferably from 0.03% to 0.7%, especially from 0.05% to 0.5%.

(26) The block copolymers as described above and below can advantageously and preferably be prepared in accordance with the disclosure given in US 2003/0109662 A1 or are commercially available as additives of the PolyFox® series available from Omnova Solutions Inc., USA, such as for example PolyFox® PF-636, PolyFox® PF-6320, PolyFox® PF-656, PolyFox® PF-650, or Polyfox® PF-7002:

(27) ##STR00015##

(28) In a preferred embodiment, the polymerizable LC material comprises one or more reactive mesogens selected from formula RMT,

(29) ##STR00016## P is a polymerizable group, Sp is a spacer group or a single bond, r2 and r3 are independently of each other 0, 1, 2, 3 or 4, R.sup.11 is P-Sp-, alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy preferably with 1 to 15 C atoms, which is more preferably optionally fluorinated. A and B denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L, preferably 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, thiophene-2,5-diyl, naphthalene-2,6-diyl, 1,2,3,4-tetrahydro-naphthalene-2,6-diyl, indane-2,5-diyl, bicyclooctylene or 1,4-cyclohexylene wherein one or two non-adjacent CH.sub.2 groups are optionally replaced by 0 and/or S, wherein these groups are unsubstituted or substituted by 1, 2, 3 or 4 groups L L is P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)OR.sup.x, —C(═O)R.sup.x, —NR.sup.xR.sup.y, —OH, —SF.sub.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.sup.x and R.sup.y independently of each other denote H or alkyl with 1 to 12 C-atoms, Z.sup.11 and Z.sup.12 denotes, in case of multiple occurrence independently of one another, —O—, —S—, —CO—, —COO—, —OCO—, —S—CO—, —CO—S—, —O—COO—, —CO—NR.sup.00—, —NR.sup.00—CO—, —NR.sup.00—CO—NR.sup.000, —NR.sup.00—CO—O—, —O—CO—NR.sup.00—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —CH.sub.2CH.sub.2—, —(CH.sub.2).sub.n1, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.2—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.00—, —CY.sup.1═CY.sup.2—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond, preferably —COO—, —OCO—, —C≡C—, or a single bond, Y.sup.1 and Y.sup.2 independently of each other denote H, F, C or CN, n is 1, 2, 3 or 4, preferably 1 or 2, most preferably 1, m is 0, 1, 2, 3 or 4, preferably 0 or 1, most preferably 0, and n1 is an integer from 1 to 10, preferably 1, 2, 3 or 4.

(30) Preferred compounds of formula RMT are those selected of formula RMTa or RMTb,

(31) ##STR00017##
wherein P is a polymerizable group, Sp is a spacer group or a single bond, r1, r2, r3 are independently of each other 0, 1, 2, 3 or 4, preferably 0, 1 or 2 and L, R.sup.11, Z.sup.12, ring B and m have one of the meanings as given above under formula RMT.

(32) Preferred compounds of formula RMTa are those selected of formula RMTa1 to RMTa6

(33) ##STR00018##
wherein L, P, Sp, and R.sup.11 are as defined in formula RMT, r1 to r3 denotes 1, 2, 3, or 4, preferably 1 or 2.

(34) Preferred compounds of formula RMTa1 to RMTa6 are selected of the following formulae

(35) ##STR00019## ##STR00020##

(36) Wherein P.sup.11 denotes selected from the group consisting of heptadiene, vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide groups, and very preferably denotes an acrylate, methacrylate or oxetane group, especially an acrylate or methacrylate group, in particular an acrylate group, and x is an integer from 0 to 12, preferably from 1 to 8, more preferably 3, 4, 5 or 6, in particular x denotes 3 or 6, especially 6 and R.sup.11 denotes alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy preferably with 1 to 15 C atoms which is more preferably optionally fluorinated and L has on each occurrence one of the meanings as given above under formula RMT.

(37) Especially preferred are the compounds of formula RMTa2, which are preferably selected from the following formulae:

(38) ##STR00021## ##STR00022## ##STR00023##

(39) Wherein R.sup.11 has one of the meanings as given above under formula RMT, preferably R.sup.11 denotes alkyl or alkoxy, more preferably, methoxy, ethoxy, propoxy, methyl, ethyl, propyl, butyl, pentyl, isopropyl or isobutyl, in particular methoxy.

(40) Preferred compounds of formula RMTb are those selected of formula RMTb0 to RMTb6

(41) ##STR00024##
wherein L, P, Sp, and R.sup.11 are as defined in formula RMT, r1 to r3 denotes 1, 2, 3, or 4, preferably 1 or 2.

(42) Preferred compounds of formula RMTb0 to RMTb6 are selected of the following formulae

(43) ##STR00025## ##STR00026##

(44) Wherein P.sup.11 denotes selected from the group consisting of heptadiene, vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide groups, and very preferably denotes an acrylate, methacrylate or oxetane group, especially an acrylate or methacrylate group, in particular an acrylate group, and x is an integer from 0 to 12, preferably from 1 to 8, more preferably 3, 4, 5 or 6, in particular x denotes 3 or 6, especially 6 and R.sup.11 denotes alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy preferably with 1 to 15 C atoms which is more preferably optionally fluorinated and L has on each occurrence one of the meanings as given above under formula RMT.

(45) Especially preferred are the compounds of formula RMTb2, which are preferably selected from the following formulae:

(46) ##STR00027## ##STR00028## ##STR00029##

(47) Wherein R.sup.11 has one of the meanings as given above under formula RMT. Preferably, R.sup.11 denotes alkyl or alkoxy.

(48) Further preferred are compounds of formula RMTb2-A1, which are selected from compounds of the following formulae

(49) ##STR00030## ##STR00031## ##STR00032##

(50) Wherein R.sup.11 has one of the meanings as given above under formula RMT, preferably R.sup.11 denotes alkyl or alkoxy, more preferably, methoxy, ethoxy, propoxy, methyl, ethyl, propyl, butyl, pentyl, isopropyl or isobutyl, in particular methoxy.

(51) Preferably, the polymerizable LC material comprises one or more, preferably two or more compounds selected from formulae RMTa2-A3 to RMTa2-A6 or RMTb2-A3, especially the polymerizable LC material comprises one or more compounds of formula RMTb2-A3, in particular, the polymerizable LC material comprises a combination of compounds of formulae RMTa2-A4 and/or RMTa2-A5 with RMTb2-A3.

(52) By utilizing one or more compounds of formula RMT in the polymerizable LC materials, the birefringence of a polymer film can be beneficially increased.

(53) The corresponding reflection bandwidth is related to birefringence by the following formula:
Bandwidth=Δn*pitch,
it can be seen that by increasing the birefringence of the cholesteric polymer film, it is possible to achieve a wider bandwidth of reflection. By utilizing compounds of formula RMT in a polymerizable LC material, it is possible to widen the reflection bandwidth significantly of a corresponding polymer film while also not negatively affecting film properties such as wet film crystallization or dewetting.

(54) The concentration of compounds of formula RMT and its subformulae, in the polymerizable LC material is preferably from 40% to 99%, more preferably from 45 to 95%, especially from 50 to 90%.

(55) The compounds of formula RMT are either commercially available from Merck KGaA, Darmstadt or can be synthesized in accordance with the procedures given for example in U.S. Pat. No. 6,514,578 or U.S. Ser. No. 15/575,415.

(56) In preferred embodiment, the polymerizable LC material comprises one or more di- or multireactive reactive mesogens that are preferably selected of formula DRM
P.sup.1-Sp.sup.1-MG-Sp.sup.2-P.sup.2  DRM
wherein P.sup.1 and P.sup.2 independently of each other denote a polymerizable group, Sp.sup.1 and Sp.sup.2 independently of each other are a spacer group or a single bond, and MG is a rod-shaped mesogenic group, which is preferably selected of formula MG
-(A.sup.1-Z.sup.1).sub.n-A.sup.2-  MG
wherein A.sup.1 and A.sup.2 denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L, L is P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)OR.sup.x, —C(═O)R.sup.x, —NR.sup.xR.sup.y, —OH, —SF.sub.5, optionally substituted silyl, aryl or heteroaryl with 1 to 12, preferably 1 to 6 C atoms, and straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12, preferably 1 to 6 C atoms, wherein one or more H atoms are optionally replaced by F or Cl, R.sup.x and R.sup.y independently of each other denote H or alkyl with 1 to 12 C-atoms, Z.sup.1 denotes, in case of multiple occurrence independently of one another, —O—, —S—, —CO—, —COO—, —OCO—, —S—CO—, —CO—S—, —O—COO—, —CO—NR.sup.x—, —NR.sup.x—CO—, —NR.sup.x—CO—NR.sup.y, —NR.sup.x—CO—O—, —O—CO—NR.sup.x—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —(CH.sub.2).sub.n1, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.2—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.x—, —CY.sup.1═CY.sup.2—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond, preferably —COO—, —OCO— or a single bond, Y.sup.1 and Y.sup.2 independently of each other denote H, F, Cl or CN, n is 1, 2, 3 or 4, preferably 1 or 2, most preferably 2, n1 is an integer from 1 to 10, preferably 1, 2, 3 or 4, however, under the condition that compounds of formula RMT are excluded from the compounds of formula DRM.

(57) Preferred groups A.sup.1 and A.sup.2 include, without limitation, furan, pyrrol, thiophene, oxazole, thiazole, thiadiazole, imidazole, phenylene, cyclohexylene, bicyclooctylene, cyclohexenylene, pyridine, pyrimidine, pyrazine, azulene, indane, fluorene, naphthalene, tetrahydronaphthalene, anthracene, phenanthrene and dithienothiophene, all of which are unsubstituted or substituted by 1, 2, 3 or 4 groups L as defined above.

(58) Particular preferred groups A.sup.1 and A.sup.2 are selected from 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, thiophene-2,5-diyl, naphthalene-2,6-diyl, 1,2,3,4-tetrahydro-naphthalene-2,6-diyl, indane-2,5-diyl, bicyclooctylene or 1,4-cyclohexylene wherein one or two non-adjacent CH.sub.2 groups are optionally replaced by O and/or S, wherein these groups are unsubstituted or substituted by 1, 2, 3 or 4 groups L as defined above.

(59) Preferred RMs of formula DRM are selected of formula DRMa

(60) ##STR00033##
wherein P.sup.0 is, in case of multiple occurrence independently of one another, a polymerizable group, preferably an acryl, methacryl, oxetane, epoxy, vinyl, heptadiene, vinyloxy, propenyl ether or styrene group, Z.sup.0 is —COO—, —OCO—, —CH.sub.2CH.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —C≡C—, —CH═CH—, —OCO—CH═CH—, —CH═CH—COO—, or a single bond, L has on each occurrence identically or differently one of the meanings given for L in formula DRM, and is preferably, in case of multiple occurrence independently of one another, selected from F, Cl, CN or optionally halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms, r is 0, 1, 2, 3 or 4, x and y are independently of each other 0 or identical or different integers from 1 to 12, z is 0 or 1, with z being 0 if the adjacent x or y is 0.

(61) Very preferred RMs of formula DRM are selected from the following formulae:

(62) ##STR00034##
wherein P.sup.0, L, r, x, y and z are as defined in formula DRMa.

(63) Especially preferred are compounds of formula DRMa1, DRMa2 and DRMa3, in particular those of formula DRMa1.

(64) The concentration of di- or multireactive RMs, preferably those of formula DRM and its subformulae, in the RM mixture is preferably from 1% to 60%, very preferably from 5 to 40%.

(65) In another preferred embodiment, the RM mixture comprises one or more monoreactive RMs. These additional monoreactive RMs are preferably selected from formula MRM:
P.sup.1—Sp.sup.1-MG-R  MRM
wherein P.sup.1, Sp.sup.1 and MG have the meanings given in formula DRM, R denotes P-Sp-, F, Cl, Br, I, —CN, —NO.sub.2, —NCO, —NCS, —OCN, —SCN, —C(═O)NR.sup.xR.sup.y, —C(═O)X, —C(═O)OR.sup.x, —C(═O)R.sup.y, —NR.sup.xR.sup.y, —OH, —SF.sub.5, optionally substituted silyl, straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12, preferably 1 to 6 C atoms, wherein one or more H atoms are optionally replaced by F or Cl, X is halogen, preferably F or Cl, and R.sup.x and R.sup.y are independently of each other H or alkyl with 1 to 12 C-atoms, however, under the condition that compounds of formula RMT are excluded from the compound of formula MRM.

(66) Preferably, the compounds of formula MRM are selected from the following formulae.

(67) ##STR00035## ##STR00036##
wherein P.sup.0, L, r, x, y and z are as defined in formula DRMa, R.sup.0 is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 or more, preferably 1 to 15 C atoms or denotes Y.sup.0 or P—(CH.sub.2).sub.y—(O).sub.z—, X.sup.0 is —O—, —S—, —CO—, —COO—, —OCO—, —O—COO—, —CO—NR.sup.01—, —NR.sup.01—CO—, —NR.sup.01—CO—NR.sup.01—, —OCH.sub.2—, —CH.sub.2O—, —SCH.sub.2—, —CH.sub.2S—, —CF.sub.2O—, —OCF.sub.2—, —CF.sub.2S—, —SCF.sub.2—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.2—, —CH═N—, —N═CH—, —N═N—, —CH═CR.sup.01—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond Y.sup.0 is F, Cl, CN, NO.sub.2, OCH.sub.3, ON, SON, SF.sub.5, or mono- oligo- or polyfluorinated alkyl or alkoxy with 1 to 4 C atoms, Z.sup.0 is —COO—, —OCO—, —CH.sub.2CH.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —CH═CH—, —OCO— CH═CH—, —CH═CH—COO—, or a single bond, A.sup.0 is, 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, or trans-1,4-cyclohexylene, R.sup.01,02 are independently of each other H, R.sup.0 or Y.sup.0, u and v are independently of each other 0, 1 or 2, w is 0 or 1,
and wherein the benzene and naphthalene rings can additionally be substituted with one or more identical or different groups L.

(68) Especially preferred are compounds of formula MRM1, MRM2, MRM3, MRM4, MRM5, MRM6, MRM7, in particular those of formula MRM1, MRM4, MRM6, and MRM7.

(69) The concentration of all monoreactive RMs, including those of formula RMT, in the polymerizable LC material is preferably from 1 to 80%, very preferably from 5 to 20%.

(70) In formulae DRM, MRM and their preferred subformulae, L is preferably selected from F, Cl, CN, NO.sub.2 or straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonlyoxy or alkoxycarbonyloxy with 1 to 12 C atoms, wherein the alkyl groups are optionally perfluorinated, or P-Sp-.

(71) Very preferably L is selected from F, Cl, CN, NO.sub.2, CH.sub.3, C.sub.2H.sub.5, C(CH.sub.3).sub.3, CH(CH.sub.3).sub.2, CH.sub.2CH(CH.sub.3)C.sub.2H.sub.5, OCH.sub.3, OC.sub.2H.sub.5, COCH.sub.3, COC.sub.2H.sub.5, COOCH.sub.3, COOC.sub.2H.sub.5, CF.sub.3, OCF.sub.3, OCHF.sub.2, OC.sub.2F.sub.5 or P-Sp-, in particular F, Cl, CN, CH.sub.3, C.sub.2H.sub.5, C(CH.sub.3).sub.3, CH(CH.sub.3).sub.2, OCH.sub.3, COCH.sub.3 or OCF.sub.3, most preferably F, Cl, CH.sub.3, C(CH.sub.3).sub.3, OCH.sub.3 or COCH.sub.3, or P-Sp-.

(72) Preferably, the polymerizable LC material according to the present invention comprises one or more chiral compounds. These chiral compounds may be non-mesogenic compounds or mesogenic compounds. Additionally, these chiral compounds, whether mesogenic or non-mesogenic, may be non-reactive, monoreactive or multireactive.

(73) Preferably the utilized chiral compounds have each alone or in combination with each other an absolute value of the helical twisting power (|HTP.sub.total|) of 20 μm.sup.−1 or more, preferably of 40 μm.sup.−1 or more, more preferably in the range of 60 μm.sup.−1 or more, most preferably in the range of 80 μm.sup.−1 or more to 260 μm.sup.−1, in particular those disclosed in WO 98/00428.

(74) Preferably, non-polymerizable chiral compounds are selected from the group of compounds of formulae C-I to C-III,

(75) ##STR00037##
the latter ones including the respective (S,S) enantiomers,
wherein E and F are each independently 1,4-phenylene or trans-1,4-cyclohexylene, v is 0 or 1, Z.sup.0 is —COO—, —OCO—, —CH.sub.2CH.sub.2— or a single bond, and R is alkyl, alkoxy or alkanoyl with 1 to 12 C atoms.

(76) Particularly preferred polymerizable LC materials that comprise one or more chiral compounds, which do not necessarily have to show a liquid crystalline phase.

(77) The compounds of formula C—II and their synthesis are described in WO 98/00428. Especially preferred is the compound CD-1, as shown in table D below. The compounds of formula C—III and their synthesis are described in GB 2 328 207.

(78) Further, typically used chiral compounds are e.g. the commercially available R/S-5011, CD-1, R/S-811 and CB-15 (from Merck KGaA, Darmstadt, Germany).

(79) The above mentioned chiral compounds R/S-5011 and CD-1 and the (other) compounds of formulae C-I, C-II and C-III exhibit a very high helical twisting power (HTP), and are therefore particularly useful for the purpose of the present invention.

(80) The polymerizable LC material preferably comprises 1 to 5, in particular 1 to 3, very preferably 1 or 2 chiral compounds, preferably selected from the above formula C-II, in particular CD-1, and/or formula C-III and/or R-5011 or S-5011, very preferably, the chiral compound is R-5011, S-5011 or CD-1.

(81) Preferably, the polymerizable LC material comprise one or more non-reactive chiral compound and/or one or more reactive chiral compounds, which are preferably selected from mono- and/or multireactive chiral compounds.

(82) Suitable mesogenic reactive chiral compounds preferably comprise one or more ring elements, linked together by a direct bond or via a linking group and, where two of these ring elements optionally may be linked to each other, either directly or via a linking group, which may be identical to or different from the linking group mentioned. The ring elements are preferably selected from the group of four-, five-, six- or seven-, preferably of five- or six-, membered rings.

(83) Preferred mono-reactive chiral compounds are selected from compounds of formula CRMa to CRMc,

(84) ##STR00038##
wherein P.sup.0* denotes a polymerizable group P Sp* denotes a spacer Sp A.sup.0 and B.sup.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.sup.1 and X.sup.2 are independently of each other —O—, —COO—, —OCO—, —O—CO—O— or a single bond, Z.sup.0* is, in case of multiple occurrence independently of one another, —COO—, —OCO—, —O—CO—O—, —OCH.sub.2—, —CH.sub.2O—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2CH.sub.2—, —(CH.sub.2).sub.4—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —CF.sub.2CF.sub.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.

(85) The compounds of formula CRMa are preferably selected from the group of compounds of formulae CRMa-1.

(86) ##STR00039##
wherein X.sup.2, A.sup.0, B.sup.0, Z.sup.0*, P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below, and (OCO) denotes —O—CO— or a single bond.

(87) Especially preferred compounds of formula CRM are selected from the group consisting of the following subformulae:

(88) ##STR00040##

(89) wherein R is —X.sup.2—(CH.sub.2).sub.x—P.sup.0* as defined in formula CRM-a, and the benzene and naphthalene rings are unsubstituted or substituted with 1, 2, 3 or 4 groups L as defined above and below.

(90) The compounds of formula CRMb are preferably selected from the group of compounds of formulae CRMb-1 to CRMb-3,

(91) ##STR00041##
wherein X.sup.2, A.sup.0, B°, Z.sup.0*, P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below.

(92) Preferred compounds of formula CRMb-1 are preferably selected from the group of compounds of formulae CRMb-1a and CRMb-1 b,

(93) ##STR00042##
wherein X.sup.2, Z.sup.0*, P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below. Preferably, in the compounds of formulae CRMb-1a and CRMb-1b, Z.sup.0 denotes OCOO, COO, OCO or a single bond. Preferably, in the compounds of formulae CRMb-1a and CRMb-1b, X.sup.2 denotes OCOO, OCO, COO or a single bond. Preferred are compounds of formula and CRMb-1 b that are selected from the following compounds,

(94) ##STR00043##
wherein P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below.

(95) The compound CRMb-1 bl wherein P.sup.0* denotes in each occurrence an acrylate group and b denotes in each occurrence 4, is especially preferred and commercially available from BASF, Germany under tradename LC756.

(96) The compounds of formula CRMc are preferably selected from the group of compounds of formulae CRMc-1,

(97) ##STR00044##
wherein X.sup.2, A.sup.0, B.sup.0, Z.sup.0*, P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below.

(98) Preferred compounds of formula CRMc-1 are preferably selected from the group of compounds of formulae CRMc-1a and CRMc-1 b,

(99) ##STR00045##
wherein X.sup.2, Z.sup.0*, P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below. Preferably, in the compounds of formulae CRMc-1a and CRMc-1b, Z.sup.0 denotes OCOO, COO, OCO or a single bond. Preferably, in the compounds of formulae CRMc-1a and CRMc-1 b, X.sup.2 denotes O, OCOO, OCO, COO or a single bond.

(100) Preferred are compounds of formula and CRMc-1a that are selected from the following compounds,

(101) ##STR00046##
wherein P.sup.0* and b have the meanings given in formula CRMa or one of the preferred meanings given above and below.

(102) The compound CRMc-1al wherein P*denotes in each occurrence an acrylate group and b denotes in each occurrence 3 or 6, and X.sup.2 denotes in each occurrence O or a single bond is especially preferred.

(103) The amount of chiral compounds in the liquid-crystalline medium is preferably from 1 to 20%, more preferably from 1 to 15%, even more preferably 1 to 10%, and most preferably 3 to 7%, by weight of the total mixture.

(104) In a preferred embodiment, the proportion of polymerizable mesogenic compounds in the polymerizable liquid-crystalline material, according to the present invention as a whole, is in the range from 30 to 99% by weight, more preferably in the range from 40 to 97% by weight and even more preferably in the range from 50 to 95% by weight.

(105) Preferably, the proportion of said mono-, di- or multireactive liquid-crystalline compounds, preferably selected from the compounds of the formulae DRM, MRM as given above and below in the polymerizable liquid-crystalline material according to the present invention as a whole, is preferably in the range from 30 to 99.9% by weight, more preferably in the range from 40 to 99.9% by weight and even more preferably in the range from 50 to 99.9% by weight.

(106) In a preferred embodiment, the proportion of di- or multireactive polymerizable mesogenic compounds in the polymerizable liquid-crystalline material according to the present invention as a whole, is preferably in the range from 1 to 70% by weight, more preferably in the range from 2 to 60% by weight and even more preferably in the range from 3 to 50% by weight.

(107) In another preferred embodiment, the proportion of monoreactive polymerizable mesogenic compounds of formula MRM excluding compounds of formula RMT in a polymerizable liquid-crystalline material according to the present invention as a whole, is, if present, preferably in the range from 1 to 50% by weight, more preferably in the range from 2 to 45% by weight and even more preferably in the range from 5 to 40% by weight.

(108) In another preferred embodiment, the proportion of multireactive polymerizable mesogenic compounds in a polymerizable liquid-crystalline material according to the present invention as a whole is, if present, preferably in the range from 1 to 30% by weight, more preferably in the range from 2 to 20% by weight and even more preferably in the range from 3 to 10% by weight.

(109) In another preferred embodiment the polymerizable LC material does not contain polymerizable mesogenic compounds having more than two polymerizable groups.

(110) In a further preferred embodiment, the polymerizable LC material comprises one or more monoreactive mesogenic compounds, preferably selected from formulae MRM-1, MRM-4, MRM-6, and/or MRM-7, one or more direactive mesogenic compounds, preferably selected from formula DRMa-1.

(111) The polymerizable LC material should in addition be of such a nature that different reflection wavelengths, in particular in the VIS light region, can be achieved by simple and targeted variation. Preferably the cholesteric pitch of the polymerizable LC material is selected such, that their wavelength of reflection is in the in the range in the infrared range of the electromagnetic spectrum i.e. in the range from of 300 nm to 900 nm, more preferably form 350 to 850 nm. In particular, the reflection wavelength of the liquid crystalline medium is in the range of 400 nm to 800 nm.

(112) The polymerizable LC material according to the present invention are prepared in a manner conventional per se, for example by mixing one or more of the above-mentioned polymerizable compounds with one or more block copolymers as described above and below, and one or more chiral compounds, both as defined above, and optionally with further liquid-crystalline compounds and/or additives, and/or solvents.

(113) In a further preferred embodiment the polymerizable LC material optionally comprises one or more additives selected from the group consisting of further polymerization initiators, antioxidants, surfactants, stabilisers, catalysts, sensitizers, inhibitors, chain-transfer agents, co-reacting monomers, reactive thinners, surface-active compounds, lubricating agents, wetting agents, dispersing agents, hydrophobing agents, adhesive agents, flow improvers, degassing or defoaming agents, deaerators, diluents, reactive diluents, auxiliaries, colourants, dyes, pigments and nanoparticles.

(114) In another preferred embodiment, the polymerizable LC material optionally comprises one or more additives selected from polymerizable non-mesogenic compounds (reactive thinners). The amount of these additives in the polymerizable LC material is preferably from 0 to 30%, very preferably from 0 to 25%.

(115) The reactive thinners used are not only substances which are referred to in the actual sense as reactive thinners, but also auxiliary compounds already mentioned above which contain one or more complementary reactive units or polymerizable groups P, for example hydroxyl, thiol-, or amino groups, via which a reaction with the polymerizable units of the liquid-crystalline compounds can take place.

(116) The substances, which are usually capable of photopolymerization, include, for example, mono-, bi- and polyfunctional compounds containing at least one olefinic double bond. Examples thereof are vinyl esters of carboxylic acids, for example of lauric, myristic, palmitic and stearic acid, and of dicarboxylic acids, for example of succinic acid, adipic acid, allyl and vinyl ethers and methacrylic and acrylic esters of monofunctional alcohols, for example of lauryl, myristyl, palmityl and stearyl alcohol, and diallyl and divinyl ethers of bifunctional alcohols, for example ethylene glycol and 1,4-butanediol.

(117) Also suitable are, for example, methacrylic and acrylic esters of polyfunctional alcohols, in particular those that contain no further functional groups, or at most ether groups, besides the hydroxyl groups. Examples of such alcohols are bifunctional alcohols, such as ethylene glycol, propylene glycol and their more highly condensed representatives, for example diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol etc., butanediol, pentanediol, hexanediol, neopentyl glycol, alkoxylated phenolic compounds, such as ethoxylated and propoxylated bisphenols, cyclohexanedimethanol, trifunctional and polyfunctional alcohols, such as glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, sorbitol, mannitol, and the corresponding alkoxylated, in particular ethoxylated and propoxylated alcohols.

(118) Other suitable reactive thinners are polyester (meth)acrylates, which are the (meth)acrylic ester of polyesterols.

(119) Examples of suitable polyesterols are those that can be prepared by esterification of polycarboxylic acids, preferably dicarboxylic acids, using polyols, preferably diols. The starting materials for such hydroxyl-containing polyesters are known to the person skilled in the art. Dicarboxylic acids which can be employed are succinic, glutaric acid, adipic acid, sebacic acid, o-phthalic acid and isomers and hydrogenation products thereof, and esterifiable and transesterifiable derivatives of said acids, for example anhydrides and dialkyl esters. Suitable polyols are the abovementioned alcohols, preferably ethyleneglycol, 1,2- and 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexanedimethanol and polyglycols of the ethylene glycol and propylene glycol type.

(120) Suitable reactive thinners are furthermore 1,4-divinylbenzene, triallyl cyanurate, acrylic esters of tricyclodecenyl alcohol of the following formula

(121) ##STR00047##
also known under the name dihydrodicyclopentadienyl acrylate, and the allyl esters of acrylic acid, methacrylic acid and cyanoacrylic acid.

(122) Of the reactive thinners, which are mentioned by way of example, those containing photopolymerizable groups are used in particular and in view of the abovementioned preferred compositions.

(123) This group includes, for example, dihydric and polyhydric alcohols, for example ethylene glycol, propylene glycol and more highly condensed representatives thereof, for example diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol etc., butanediol, pentanediol, hexanediol, neopentyl glycol, cyclohexanedimethanol, glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, sorbitol, mannitol and the corresponding alkoxylated, in particular ethoxylated and propoxylated alcohols.

(124) The group furthermore also includes, for example, alkoxylated phenolic compounds, for example ethoxylated and propoxylated bisphenols.

(125) These reactive thinners may furthermore be, for example, epoxide or urethane (meth)acrylates.

(126) Epoxide (meth)acrylates are, for example, those as obtainable by the reaction, known to the person skilled in the art, of epoxidized olefins or poly- or diglycidyl ether, such as bisphenol A diglycidyl ether, with (meth)acrylic acid.

(127) Urethane (meth)acrylates are, in particular, the products of a reaction, likewise known to the person skilled in the art, of hydroxylalkyl (meth)acrylates with poly- or diisocyanates.

(128) Such epoxide and urethane (meth)acrylates are included amongst the compounds listed above as “mixed forms”.

(129) If reactive thinners are used, their amount and properties must be matched to the respective conditions in such a way that, on the one hand, a satisfactory desired effect, for example the desired colour of the composition according to the invention, is achieved, but, on the other hand, the phase behaviour of the liquid-crystalline composition is not excessively impaired. The low-crosslinking (high-crosslinking) liquid-crystalline compositions can be prepared, for example, using corresponding reactive thinners, which have a relatively low (high) number of reactive units per molecule.

(130) The group of diluents include, for example:

(131) C.sub.1-C.sub.4-alcohols, for example methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol, sec-butanol and, in particular, the C.sub.5-C.sub.12-alcohols n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol, n-undecanol and n-dodecanol, and isomers thereof, glycols, for example 1,2-ethylene glycol, 1,2- and 1,3-propylene glycol, 1,2-, 2,3- and 1,4-butylene glycol, di- and triethylene glycol and di- and tripropylene glycol, ethers, for example methyl tert-butyl ether, 1,2-ethylene glycol mono- and dimethyl ether, 1,2-ethylene glycol mono- and -diethylether, 3-methoxypropanol, 3-isopropoxypropanol, tetrahydrofuran and dioxane, ketones, for example acetone, methyl ethyl ketone, methyl isobutyl ketone and diacetone alcohol (4-hydroxy-4-methyl-2-pentanone), C.sub.1-C.sub.5-alkyl esters, for example methyl acetate, ethyl acetate, propyl acetate, butyl acetate and amyl acetate, aliphatic and aromatic hydrocarbons, for example pentane, hexane, heptane, octane, isooctane, petroleum ether, toluene, xylene, ethylbenzene, tetralin, decalin, dimethylnaphthalene, white spirit, Shellsol® and Solvesso® mineral oils, for example gasoline, kerosine, diesel oil and heating oil, but also natural oils, for example olive oil, soya oil, rapeseed oil, linseed oil and sunflower oil.

(132) It is of course also possible to use mixtures of these diluents in the compositions according to the invention.

(133) So long as there is at least partial miscibility, these diluents can also be mixed with water. Examples of suitable diluents here are C1-C4-alcohols, for example methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol and sec-butanol, glycols, for example 1,2-ethylene glycol, 1,2- and 1,3-propylene glycol, 1,2-, 2,3- and 1,4-butylene glycol, di- and triethylene glycol, and di- and tripropylene glycol, ethers, for example tetrahydrofuran and dioxane, ketones, for example acetone, methyl ethyl ketone and diacetone alcohol (4-hydroxy-4-methyl-2-pentanone), and C1-C4-alkyl esters, for example methyl, ethyl, propyl and butyl acetate.

(134) The diluents are optionally employed in a proportion of from about 0 to 10.0% by weight, preferably from about 0 to 5.0% by weight, based on the total weight of the polymerizable LC material.

(135) The antifoams and deaerators (c1)), lubricants and flow auxiliaries (c2)), thermally curing or radiation-curing auxiliaries (c3)), substrate wetting auxiliaries (c4)), wetting and dispersion auxiliaries (c5)), hydrophobicizing agents (c6)), adhesion promoters (c7)) and auxiliaries for promoting scratch resistance (c8)) cannot strictly be delimited from one another in their action.

(136) For example, lubricants and flow auxiliaries often also act as antifoams and/or deaerators and/or as auxiliaries for improving scratch resistance. Radiation-curing auxiliaries can also act as lubricants and flow auxiliaries and/or deaerators and/or as substrate wetting auxiliaries. In individual cases, some of these auxiliaries can also fulfil the function of an adhesion promoter (c8)).

(137) Corresponding to the above-said, a certain additive can therefore be classified in a number of the groups c1) to c8) described below.

(138) The antifoams in group c1) include silicon-free and silicon-containing polymers. The silicon-containing polymers are, for example, unmodified or modified polydialkylsiloxanes or branched copolymers, comb or block copolymers comprising polydialkylsiloxane and polyether units, the latter being obtainable from ethylene oxide or propylene oxide.

(139) The deaerators in group c1) include, for example, organic polymers, for example polyethers and polyacrylates, dialkylpolysiloxanes, in particular dimethylpolysiloxanes, organically modified polysiloxanes, for example arylalkyl-modified polysiloxanes, and fluorosilicones.

(140) The action of the antifoams is essentially based on preventing foam formation or destroying foam that has already formed. Antifoams essentially work by promoting coalescence of finely divided gas or air bubbles to give larger bubbles in the medium to be deaerated, for example the compositions according to the invention, and thus accelerate escape of the gas (of the air). Since antifoams can frequently also be employed as deaerators and vice versa, these additives have been included together under group c1).

(141) Such auxiliaries are, for example, commercially available from Tego as TEGO® Foamex 800, TEGO® Foamex 805, TEGO® Foamex 810, TEGO® Foamex 815, TEGO® Foamex 825, TEGO® Foamex 835, TEGO® Foamex 840, TEGO® Foamex 842, TEGO® Foamex 1435, TEGO® Foamex 1488, TEGO® Foamex 1495, TEGO® Foamex 3062, TEGO® Foamex 7447, TEGO® Foamex 8020, Tego® Foamex N, TEGO® Foamex K 3, TEGO® Antifoam 2-18, TEGO® Antifoam 2-18, TEGO® Antifoam 2-57, TEGO® Antifoam 2-80, TEGO® Antifoam 2-82, TEGO® Antifoam 2-89, TEGO® Antifoam 2-92, TEGO® Antifoam 14, TEGO® Antifoam 28, TEGO® Antifoam 81, TEGO® Antifoam D 90, TEGO® Antifoam 93, TEGO® Antifoam 200, TEGO® Antifoam 201, TEGO® Antifoam 202, TEGO® Antifoam 793, TEGO® Antifoam 1488, TEGO® Antifoam 3062, TEGOPREN® 5803, TEGOPREN® 5852, TEGOPREN® 5863, TEGOPREN® 7008, TEGO® Antifoam 1-60, TEGO® Antifoam 1-62, TEGO® Antifoam 1-85, TEGO® Antifoam 2-67, TEGO® Antifoam WM 20, TEGO® Antifoam 50, TEGO® Antifoam 105, TEGO® Antifoam 730, TEGO® Antifoam MR 1015, TEGO® Antifoam MR 1016, TEGO® Antifoam 1435, TEGO® Antifoam N, TEGO® Antifoam KS 6, TEGO® Antifoam KS 10, TEGO® Antifoam KS 53, TEGO® Antifoam KS 95, TEGO® Antifoam KS 100, TEGO® Antifoam KE 600, TEGO® Antifoam KS 911, TEGO® Antifoam MR 1000, TEGO® Antifoam KS 1100, Tego® Airex 900, Tego® Airex 910, Tego® Airex 931, Tego® Airex 935, Tego® Airex 936, Tego® Airex 960, Tego® Airex 970, Tego® Airex 980 and Tego® Airex 985 and from BYK as BYK®-011, BYK®-019, BYK®-020, BYK®-021, BYK®-022, BYK®-023, BYK®-024, BYK®-025, BYK®-027, BYK®-031, BYK®-032, BYK®-033, BYK®-034, BYK®-035, BYK®-036, BYK®-037, BYK®-045, BYK®-051, BYK®-052, BYK®-053, BYK®-055, BYK®-057, BYK®-065, BYK®-066, BYK®-070, BYK®-080, BYK®-088, BYK®-141 and BYK®-A 530.

(142) The auxiliaries in group c1) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 2.0% by weight, based on the total weight of the polymerizable LC material.

(143) In group c2), the lubricants and flow auxiliaries typically include silicon-free, but also silicon-containing polymers, for example polyacrylates or modifiers, low-molecular-weight polydialkylsiloxanes. The modification consists in some of the alkyl groups having been replaced by a wide variety of organic radicals. These organic radicals are, for example, polyethers, polyesters or even long-chain (fluorinated)alkyl radicals, the former being used the most frequently.

(144) The polyether radicals in the correspondingly modified polysiloxanes are usually built up from ethylene oxide and/or propylene oxide units. Generally, the higher the proportion of these alkylene oxide units in the modified polysiloxane, the more hydrophilic is the resultant product.

(145) Such auxiliaries are, for example, commercially available from Tego as TEGO® Glide 100, TEGO® Glide ZG 400, TEGO® Glide 406, TEGO® Glide 410, TEGO® Glide 411, TEGO® Glide 415, TEGO® Glide 420, TEGO® Glide 435, TEGO® Glide 440, TEGO® Glide 450, TEGO® Glide A 115, TEGO® Glide B 1484 (can also be used as antifoam and deaerator), TEGO® Flow ATF, TEGO® Flow 300, TEGO® Flow 460, TEGO® Flow 425 and TEGO® Flow ZFS 460. Suitable radiation-curable lubricants and flow auxiliaries, which can also be used to improve the scratch resistance, are the products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, TEGO® Rad 2600 and TEGO® Rad 2700, which are likewise obtainable from TEGO.

(146) Such-auxiliaries are also available, for example, from BYK as BYK®-300 BYK®-306, BYK®-307, BYK®-310, BYK®-320, BYK®-333, BYK®-341, Byk® 354, Byk®361, Byk®361N, BYK®388.

(147) Such-auxiliaries are also available, for example, from 3M as FC4430®.

(148) Such-auxiliaries are also available, for example, from Cytonix as FluorN®561 or FluorN®562.

(149) Such-auxiliaries are also available, for example, from Merck KGaA as Tivida® FL 2300 and Tivida® FL 2500

(150) The auxiliaries in group c2) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 2.0% by weight, based on the total weight of the polymerizable LC material.

(151) In group c3), the radiation-curing auxiliaries include, in particular, polysiloxanes having terminal double bonds which are, for example, a constituent of an acrylate group. Such auxiliaries can be crosslinked by actinic or, for example, electron radiation. These auxiliaries generally combine a number of properties together. In the uncrosslinked state, they can act as antifoams, deaerators, lubricants and flow auxiliaries and/or substrate wetting auxiliaries, while, in the crosslinked state, they increase, in particular, the scratch resistance, for example of coatings or films which can be produced using the compositions according to the invention. The improvement in the gloss properties, for example of precisely those coatings or films, is regarded essentially as a consequence of the action of these auxiliaries as antifoams, deaerators and/or lubricants and flow auxiliaries (in the uncrosslinked state).

(152) Examples of suitable radiation-curing auxiliaries are the products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, TEGO® Rad 2600 and TEGO® Rad 2700 available from TEGO and the product BYK®-371 available from BYK.

(153) Thermally curing auxiliaries in group c3) contain, for example, primary OH groups, which are able to react with isocyanate groups, for example of the binder.

(154) Examples of thermally curing auxiliaries, which can be used, are the products BYK®-370, BYK®-373 and BYK®-375 available from BYK.

(155) The auxiliaries in group c3) are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the polymerizable LC material.

(156) The substrate wetting auxiliaries in group c4) serve, in particular, to increase the wettability of the substrate to be printed or coated, for example, by printing inks or coating compositions, for example compositions according to the invention. The generally attendant improvement in the lubricant and flow behaviour of such printing inks or coating compositions has an effect on the appearance of the finished (for example crosslinked) print or coating.

(157) A wide variety of such auxiliaries are commercially available, for example from Tego as TEGO® Wet KL 245, TEGO® Wet 250, TEGO® Wet 260 and TEGO® Wet ZFS 453 and from BYK as BYK®-306, BYK®-307, BYK®-310, BYK®-333, BYK®-344, BYK®-345, BYK®-346 and Byk®-348.

(158) The auxiliaries in group c4) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 1.5% by weight, based on the total weight of the liquid-crystalline composition.

(159) The wetting and dispersion auxiliaries in group c5) serve, in particular, to prevent the flooding and floating and the sedimentation of pigments and are therefore, if necessary, suitable in particular in pigmented compositions.

(160) These auxiliaries stabilize pigment dispersions essentially through electrostatic repulsion and/or steric hindrance of the pigment particles containing these additives, where, in the latter case, the interaction of the auxiliary with the ambient medium (for example binder) plays a major role.

(161) Since the use of such wetting and dispersion auxiliaries is common practice, for example in the technical area of printing inks and paints, the selection of a suitable auxiliary of this type generally does not present the person skilled in the art with any difficulties, if they are used.

(162) Such wetting and dispersion auxiliaries are commercially available, for example from Tego, as TEGO® Dispers 610, TEGO® Dispers 610 S, TEGO® Dispers 630, TEGO® Dispers 700, TEGO® Dispers 705, TEGO® Dispers 710, TEGO® Dispers 720 W, TEGO® Dispers 725 W, TEGO® Dispers 730 W, TEGO® Dispers 735 W and TEGO® Dispers 740 W and from BYK as Disperbyk®, Disperbyk®-107, Disperbyk®-108, Disperbyk®-110, Disperbyk®-111, Disperbyk®-115, Disperbyk®-130, Disperbyk®-160, Disperbyk®-161, Disperbyk®-162, Disperbyk®-163, Disperbyk®-164, Disperbyk®-165, Disperbyk®-166, Disperbyk®-167, Disperbyk®-170, Disperbyk®-174, Disperbyk®-180, Disperbyk®-181, Disperbyk®-182, Disperbyk®-183, Disperbyk®-184, Disperbyk®-185, Disperbyk®-190, Anti-Terra®-U, Anti-Terra®-U 80, Anti-Terra®-P, Anti-Terra®-203, Anti-Terra®-204, Anti-Terra®-206, BYK®-151, BYK®-154, BYK®-155, BYK®-P 104 S, BYK®-P 105, Lactimon®, Lactimon®-WS and Bykumen®.

(163) The amount of the auxiliaries in group c5) used on the mean molecular weight of the auxiliary. In any case, a preliminary experiment is therefore advisable, but this can be accomplished simply by the person skilled in the art.

(164) The hydrophobicizing agents in group c6) can be used to give water-repellent properties to prints or coatings produced, for example, using compositions according to the invention. This prevents or at least greatly suppresses swelling due to water absorption and thus a change in, for example, the optical properties of such prints or coatings. In addition, when the composition is used, for example, as a printing ink in offset printing, water absorption can thereby be prevented or at least greatly reduced.

(165) Such hydrophobicizing agents are commercially available, for example, from Tego as Tego® Phobe WF, Tego® Phobe 1000, Tego® Phobe 1000 S, Tego® Phobe 1010, Tego® Phobe 1030, Tego® Phobe 1010, Tego® Phobe 1010, Tego® Phobe 1030, Tego® Phobe 1040, Tego® Phobe 1050, Tego® Phobe 1200, Tego® Phobe 1300, Tego® Phobe 1310 and Tego® Phobe 1400.

(166) The auxiliaries in group c6) are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the polymerizable LC material.

(167) Further adhesion promoters from group c7) serve to improve the adhesion of two interfaces in contact. It is directly evident from this that essentially the only fraction of the adhesion promoter that is effective is that located at one or the other or at both interfaces. If, for example, it is desired to apply liquid or pasty printing inks, coating compositions or paints to a solid substrate, this generally means that the adhesion promoter must be added directly to the latter or the substrate must be pre-treated with the adhesion promoters (also known as priming), i.e. this substrate is given modified chemical and/or physical surface properties.

(168) If the substrate has previously been primed with a primer, this means that the interfaces in contact are that of the primer on the one hand and of the printing ink or coating composition or paint on the other hand. In this case, not only the adhesion properties between the substrate and the primer, but also between the substrate and the printing ink or coating composition or paint play a part in adhesion of the overall multilayer structure on the substrate.

(169) Adhesion promoters in the broader sense which may be mentioned are also the substrate wetting auxiliaries already listed under group c4), but these generally do not have the same adhesion promotion capacity.

(170) In view of the widely varying physical and chemical natures of substrates and of printing inks, coating compositions and paints intended, for example, for their printing or coating, the multiplicity of adhesion promoter systems is not surprising.

(171) Adhesion promoters based on silanes are, for example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-aminoethyl-3-aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane and vinyltrimethoxysilane. These and other silanes are commercially available from Hüls, for example under the tradename DYNASILAN®.

(172) Corresponding technical information from the manufacturers of such additives should generally be used or the person skilled in the art can obtain this information in a simple manner through corresponding preliminary experiments.

(173) However, if these additives are to be added as auxiliaries from group c7) to the polymerizable LC materials according to the invention, their proportion optionally corresponds to from about 0 to 5.0% by weight, based on the total weight of the polymerizable LC material. These concentration data serve merely as guidance, since the amount and identity of the additive are determined in each individual case by the nature of the substrate and of the printing/coating composition. Corresponding technical information is usually available from the manufacturers of such additives for this case or can be determined in a simple manner by the person skilled in the art through corresponding preliminary experiments.

(174) The auxiliaries for improving the scratch resistance in group c8) include, for example, the abovementioned products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, TEGO® Rad 2600 and TEGO® Rad 2700, which are available from Tego.

(175) For these auxiliaries, the amount data given for group c3) are likewise suitable, i.e. these additives are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the liquid-crystalline composition.

(176) Examples that may be mentioned of further light, heat and/or oxidation stabilizers are the following:

(177) alkylated monophenols, such as 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2-(α-methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which have a linear or branched side chain, for example 2,6-dinonyl-4-methylphenol, 2,4-dimethyl-6-(1′-methylundec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methylheptadec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methyltridec-1′-yl)phenol and mixtures of these compounds, alkylthiomethylphenols, such as 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol and 2,6-didodecylthiomethyl-4-nonylphenol,
Hydroquinones and alkylated hydroquinones, such as 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydrocrainone, 2,6-diphenyl-4-octadecyloxyphenol, 2,6-di-tert-butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenyl stearate and bis(3,5-di-tert-butyl-4-hydroxyphenyl)adipate,
Tocopherols, such as α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol and mixtures of these compounds, and tocopherol derivatives, such as tocopheryl acetate, succinate, nicotinate and polyoxyethylenesuccinate (“tocofersolate”),
hydroxylated diphenyl thioethers, such as 2,2′-thiobis(6-tert-butyl-4-methylphenol), 2,2′-thiobis(4-octylphenol), 4,4′-thiobis(6-tert-butyl-3-methylphenol), 4,4′-thiobis(6-tert-butyl-2-methylphenol), 4,4′-thiobis(3,6-di-sec-amylphenol) and 4,4′-bis(2,6-dimethyl-4-hydroxyphenyl)disulfide,
Alkylidenebisphenols, such as 2,2′-methylenebis(6-tert-butyl-4-methylphenol), 2,2′-methylenebis(6-tert-butyl-4-ethylphenol), 2,2′-methylenebis[4-methyl-6-(α-methylcyclohexyl)phenol], 2,2′-methylenebis(4-methyl-6-cyclohexylphenol), 2,2′-methylenebis(6-nonyl-4-methylphenol), 2,2′-methylenebis(4,6-di-tert-butylphenol), 2,2-ethylidenebis(4,6-di-tert-butylphenol), 2,2′-ethylidenebis(6-tert-butyl-4-isobutylphenol), 2,2′-methylenebis[6-(α-methylbenzyl)-4-nonylphenol], 2,2′-methylenebis[6-(α,α-dimethylbenzyl)-4-nonylphenol], 4,4′-methylenebis(2,6-di-tert-butylphenol), 4,4′-methylenebis(6-tert-butyl-2-methylphenol), 1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol, 1,1,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-3-n-dodecyl-mercaptobutane, ethylene glycol bis[3,3-bis(3′-tert-butyl-4′-hydroxyphenyl)butyrate], bis(3-tert-butyl-4-hydroxy-5-methylphenyl)dicyclopentadiene, bis[2-(3′-tert-butyl-2′-hydroxy-5′-methylbenzyl)-6-tert-butyl-4-methylphenyl]terephthalate, 1,1-bis(3,5-dimethyl-2-hydroxyphenyl)butane, 2,2-bis(3,5-di-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-4-n-dodecyl-mercaptobutane and 1,1,5,5-tetrakis(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane,
O—, N- and S-benzyl compounds, such as 3,5,3′,5′-tetra-tert-butyl-4,4′-dihydroxydibenzyl ether, octadecyl 4-hydroxy-3,5-dimethylbenzylmercaptoacetate, tridecyl 4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine, bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate, bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide and isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate,
aromatic hydroxybenzyl compounds, such as 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethyl-benzene, 1,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethyl-benzene and 2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol,
Triazine compounds, such as 2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,3,5-triazine, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,2,3-triazine, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1,3,5-triazine, 1,3,5-tris-(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexahydro-1,3,5-triazine, 1,3,5-tris(3,5-dicyclohexyl-4-hydroxybenzyl)isocyanurate and 1,3,5-tris(2-hydroxyethyl)isocyanurate,
Benzylphosphonates, such as dimethyl 2,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate and dioctadecyl 5-tert-butyl-4-hydroxy-3-methylbenzylphosphonate,
Acylaminophenols, such as 4-hydroxylauroylanilide, 4-hydroxystearoylanilide and octyl N-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate,
Propionic and acetic esters, for example of monohydric or polyhydric alcohols, such as methanol, ethanol, n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxalamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane and 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]-octane,
Propionamides based on amine derivatives, such as N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamine, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)trimethylenediamine and N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazine,
Ascorbic acid (Vitamin C) and ascorbic acid derivatives, such as ascorbyl palmitate, laurate and stearate, and ascorbyl sulfate and phosphate,
Antioxidants based on amine compounds, such as N,N′-diisopropyl-p-phenylenediamine, N,N′-di-sec-butyl-p-phenylenediamine, N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine, N,N′-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine, N,N′-bis(1-methylheptyl)-p-phenylenediamine, N,N′-dicyclohexyl-p-phenylenediamine, N,N′-diphenyl-p-phenylenediamine, N,N′-bis(2-naphthyl)-p-phenylenediamine, N-isopropyl-N′-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine, N-(1-methylheptyl)-N′-phenyl-p-phenylenediamine, N-cyclohexyl-N′-phenyl-p-phenylenediamine, 4-(p-toluenesulfamoyl)diphenylamine, N,N′-dimethyl-N,N′-di-sec-butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4-isopropoxydiphenylamine, N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine, N-phenyl-2-naphthylamine, octyl-substituted diphenylamine, such as p,p′-di-tert-octyldiphenylamine, 4-n-butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol, 4-octadecanoylaminophenol, bis[4-methoxyphenyl)amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, N,N,N′,N′-tetramethyl-4,4′-diaminodiphenylmethane, 1,2-bis[(2-methylphenyl)amino]ethane, 1,2-bis(phenylamino)propane, (o-tolyl)biguanide, bis[4-(1′,3′-dimethylbutyl)phenyl]amine, tert-octyl-substituted N-phenyl-1-naphthylamine, a mixture of mono- and dialkylated tert-butyl/tert-octyldiphenylamine, a mixture of mono- and dialkylated nonyldiphenylamine, a mixture of mono- and dialkylated dodecyldiphenylamine, a mixture of mono- and dialkylated isopropyl/isohexyldiphenylamine, a mixture of mono- and dialkylated tert-butyldiphenylamine, 2,3-dihydro-3,3-dimethyl-4H-1,4-benzothiazine, phenothiazine, a mixture of mono- and dialkylated tert-butyl/tert-octylphenothiazine, a mixture of mono- and dialkylated tert-octylphenothiazine, N-allylphenothiazine, N,N,N′,N′-tetraphenyl-1,4-diaminobut-2-ene, N,N-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine, bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate, 2,2,6,6-tetramethylpiperidin-4-one and 2,2,6,6-tetramethylpiperidin-4-ol,
Phosphines, phosphites and phosphonites, such as triphenylphosnine triphenylphosphite, diphenyl alkyl phosphite, phenyl dialkyl phosphite, tris(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, diisodecyloxy pentaerythritol diphosphite, bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyl))pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl)4,4′-biphenylenediphosphonite, 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]-1,3,2-dioxaphosphocine, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz[d,g]-1,3,2-dioxaphosphocine, bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite and bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite,
2-(2′-Hydroxyphenyl)benzotriazoles, such as 2-(2′-hydroxy-5′-methylphenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl)-5-chlorobenzotriazole, 2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(2′-hydroxy-4′-octyloxyphenyl)benzotriazole, 2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole, 2-(3,5′-bis-(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole, a mixture of 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxy phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxy phenyl)benzotriazole, 2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole and 2-(3′-tert-butyl-2′-hydroxy-5′-(2-isooctyloxycarbonylethyl)phenyl benzotriazole, 2,2′-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazol-2-ylphenol]; the product of complete esterification of 2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazole with polyethylene glycol 300;
sulfur-containing peroxide scavengers and sulfur-containing antioxidants, such as esters of 3,3′-thiodipropionic acid, for example the lauryl, stearyl, myristyl and tridecyl esters, mercaptobenzimidazole and the zinc salt of 2-mercaptobenzimidazole, dibutylzinc dithiocarbamates, dioctadecyl disulfide and pentaerythritol tetrakis(β-dodecylmercapto)propionate,
2-hydroxybenzophenones, such as the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decycloxy, 4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxy and 2′-hydroxy-4,4′-dimethoxy derivatives,
Esters of unsubstituted and substituted benzoic acids, such as 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoylresorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl-3,5-di-tert-butyl-4-hydroxybenzoate and 2-methyl-4,6-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate,
Acrylates, such as ethyl α-cyano-β,β-diphenylacrylate, isooctyl α-cyano-β,β-diphenylacrylate, methyl α-methoxycarbonylcinnamate, methyl α-cyano-β-methyl-p-methoxycinnamate, butyl-α-cyano-β-methyl-p-methoxycinnamate and methyl-α-methoxycarbonyl-p-methoxycinnamate, sterically hindered amines, such as bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(2,2,6,6-tetramethylpiperidin-4-yl)succinate, bis(1,2,2,6,6-pentamethylpiperidin-4-yl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(1,2,2,6,6-pentamethylpiperidin-4-yl)-n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensation product of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, the condensation product of N,N′-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, tris(2,2,6,6-tetramethylpiperidin-4-yl)nitrilotriacetate, tetrakis(2,2,6,6-tetramethylpiperidin-4-yl)1,2,3,4-butanetetracarboxylate, 1,1′-(1,2-ethylene)bis(3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, bis(1,2,2,6,6-pentamethylpiperidin-4-yl)2-n-butyl-2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonate, 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione, bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)succinate, the condensation product of N,N′-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, the condensation product of 2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidin-4-yl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane, the condensation product of 2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidin-4-yl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]-decane-2,4-dione, 3-dodecyl-1-(2,2,6,6-tetramethylpiperidin-4-yl)pyrrolidine-2,5-dione, 3-dodecyl-1-(1,2,2,6,6-pentamethylpiperidin-4-yl)pyrrolidine-2,5-dione, a mixture of 4-hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine, the condensation product of N,N′-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, the condensation product of 1,2-bis(3-aminopropylamino)ethane and 2,4,6-trichloro-1,3,5-triazine, 4-butylamino-2,2,6,6-tetramethylpiperidine, N-(2,2,6,6-tetramethylpiperidin-4-yl)-n-dodecylsuccinimide, N-(1,2,2,6,6-pentamethylpiperidin-4-yl)-n-dodecylsuccinimide, 2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4.5]-decane, the condensation product of 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro-[4.5]decane and epichlorohydrin, the condensation products of 4-amino-2,2,6,6-tetramethylpiperidine with tetramethylolacetylenediureas and poly(methoxypropyl-3-oxy)-[4(2,2,6,6-tetramethyl)piperidinyl]-siloxane,
Oxalamides, such as 4,4′-dioctyloxyoxanilide, 2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butoxanilide, 2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethyloxanilide, N,N′-bis(3-dimethylaminopropyl)oxalamide, 2-ethoxy-5-tert-butyl-2′-ethoxanilide and its mixture with 2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, and mixtures of ortho-, para-methoxy-disubstituted oxanilides and mixtures of ortho- and para-ethoxy-disubstituted oxanilides, and
2-(2-hydroxyphenyl)-1,3,5-triazines, such as 2,4,6-tris-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-butyloxypropoxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-octyloxypropoxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-hexyloxyphenyl)-4,6-diphenyl-1,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine, 2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]-1,3,5-triazine and 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine.

(178) In another preferred embodiment, the polymerizable LC material comprises one or more specific antioxidant additives, preferably selected from the Irganox® series, e.g. the commercially available antioxidants Irganox®1076 and Irganox®1010, from Ciba, Switzerland.

(179) In another preferred embodiment, the polymerizable LC material comprises a combination of one or more, more preferably of two or more photoinitiators, for example, selected from the commercially available Irgacure® or Darocure® (Ciba AG) series, in particular, Irgacure 127, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure 817, Irgacure 907, Irgacure 1300, Irgacure, Irgacure 2022, Irgacure 2100, Irgacure 2959, or Darcure TPO, further selected from the commercially available OXE02 (Ciba AG), NCI 930, N1919T (Adeka), SPI-03 or SPI-04 (Samyang).

(180) The concentration of the polymerization initiator(s) as a whole in the polymerizable LC material is preferably from 0.5 to 10%, very preferably from 0.8 to 8%, more preferably 1 to 6%.

(181) In a preferred embodiment, the polymerizable LC material is dissolved in a suitable solvent, which are preferably selected from organic solvents.

(182) The solvents are preferably selected from ketones such as acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone or cyclohexanone; acetates such as methyl, ethyl or butyl acetate or methyl acetoacetate; alcohols such as methanol, ethanol or isopropyl alcohol; aromatic solvents such as toluene or xylene; alicyclic hydrocarbons such as cyclopentane or cyclohexane; halogenated hydrocarbons such as di- or trichloromethane; glycols or their esters such as PGMEA (propyl glycol monomethyl ether acetate), γ-butyrolactone. It is also possible to use binary, ternary or higher mixtures of the above solvents. In particular, for multilayer applications, methyl iso butyl ketone is the preferred utilized solvent

(183) In case the polymerizable LC material contains one or more solvents, the total concentration of all solids, including the RMs, in the solvent(s) is preferably from 10 to 60%, more preferably from 20 to 50%, in particular from 30 to 45%

(184) Preferably, the polymerizable LC material comprises besides one or more block copolymers, a) one or more polymerizable mesogenic compounds of formula RMT and corresponding subformulae, b) optionally one or more multi- or direactive polymerizable mesogenic compounds, preferably selected from compounds of formula DRM and corresponding subformulae, c) one or more chiral mesogenic compounds, preferably selected from compounds of formula CRMa to CRMc, more preferably of CRMb, and its subformulae, d) optionally one or more monoreactive mesogens, preferably selected from compounds of formula MRM and corresponding subformulae, e) optionally one or more photoinitiators, f) optionally one or more antioxidative additives, g) optionally one or more adhesion promotors, h) optionally one or more surfactants, i) optionally one or more mono-, di- or multireactive polymerizable non-mesogenic compounds, j) optionally one or more dyes showing an absorption maximum at the wavelength used to initiate photo polymerization, k) optionally one or more chain transfer agents, l) optionally one or more further stabilizers, m) optionally one or more lubricants and flow auxiliaries, and n) optionally one or more diluents, o) optionally a non-polymerizable nematic component, p) optionally one or more organic solvents.

(185) More preferably, the polymerizable LC material comprises, a) one or more block copolymers as given above, or its corresponding preferred subformulae, b) one or more, preferably two or more polymerizable mesogenic compounds of formula RMT and corresponding subformulae, preferably selected from compounds of subformulae RMTa2-A4, and/or RMTa2-A5 and/or RMTb-A3 c) one or more, preferably two or more, direactive polymerizable mesogenic compounds, preferably selected from the compounds of formula DRMa-1, d) optionally one or more, preferably two or more, monoreactive polymerizable mesogenic compounds, preferably selected from compounds of formulae MRM-1, and/or MRM-4, and/or MRM-6, and/or MRM-7, e) optionally one or more chiral mesogenic compounds of formula CRMb, in particular of formula CRMb-1 bl, f) optionally one or more antioxidative additives, preferably selected from esters of unsubstituted and substituted benzoic acids, in particular Irganox®1076, and if present, preferably in an amount of 0.01 to 2% by weight, very preferably 0.05 to 1% by weight, g) optionally one or more photoinitiators, preferably Irgacure®907, and/or SPI-3 h) optionally one or more organic solvents, preferably methyl isobutyl ketone.

(186) The invention further relates to a method of preparing a polymer film by providing a layer of a polymerizable LC material as described above and below onto a substrate, polymerizing the polymerizable components of the polymerizable LC material by photopolymerization, and optionally removing the polymerized LC material from the substrate and/or optionally providing it onto another substrate.

(187) This polymerizable LC material can be coated or printed onto the substrate, for example by spin-coating, printing, or other known techniques, and the solvent is evaporated off before polymerization. In most cases, it is suitable to heat the mixture in order to facilitate the evaporation of the solvent.

(188) The polymerizable LC material can be applied onto a substrate by conventional coating techniques like spin coating, bar coating or blade coating. It can also be applied to the substrate by conventional printing techniques which are known to the expert, like for example screen printing, offset printing, reel-to-reel printing, letter press printing, gravure printing, rotogravure printing, flexographic printing, intaglio printing, pad printing, heat-seal printing, ink-jet printing or printing by means of a stamp or printing plate.

(189) Suitable substrate materials and substrates are known to the expert and described in the literature, as for example conventional substrates used in the optical films industry, such as glass or plastic. Especially suitable and preferred substrates for polymerization are polyester such as polyethyleneterephthalate (PET) or polyethylenenaphthalate (PEN), polyvinylalcohol (PVA), polycarbonate (PC) triacetylcellulose (TAC), or cyclo olefin polymers (COP), or commonly known color filter materials, in particular triacetylcellulose (TAC), cyclo olefin polymers (COP), or commonly known colour filter materials.

(190) The polymerizable LC material preferably exhibits a uniform alignment throughout the whole layer. Preferably, the polymerizable LC material exhibits a uniform planar, a uniform homeotropic, uniform cholesteric or patterned alignment.

(191) The Friedel-Creagh-Kmetz rule can be used to predict whether a mixture will adopt planar or homeotropic alignment, by comparing the surface energies of the RM layer (γ.sub.RM) and the substrate (γ.sub.s):

(192) If γ.sub.RM>γ.sub.s the reactive mesogenic compounds will display homeotropic alignment, If γ.sub.RM<γ.sub.s the reactive mesogenic compounds will display homogeneous alignment.

(193) Without to be bound by theory, when the surface energy of a substrate is relatively low, the intermolecular forces between the reactive mesogens are stronger than the forces across the RM-substrate interface and consequently, reactive mesogens align perpendicular to the substrate (homeotropic alignment) in order to maximise the intermolecular forces.

(194) Homeotropic alignment can also be achieved by using amphiphilic materials; they can be added directly to the polymerizable LC material, or the substrate can be treated with these materials in the form of a homeotropic alignment layer. The polar head of the amphiphilic material chemically bonds to the substrate, and the hydrocarbon tail points perpendicular to the substrate. Intermolecular interactions between the amphiphilic material and the RMs promote homeotropic alignment. Commonly used amphiphilic surfactants are described above.

(195) Another method used to promote homeotropic alignment is to apply corona discharge treatment to plastic substrates, generating alcohol or ketone functional groups on the substrate surface. These polar groups can interact with the polar groups present in RMs or surfactants to promote homeotropic alignment.

(196) When the surface tension of the substrate is greater than the surface tension of the RMs, the force across the interface dominates. The interface energy is minimised if the reactive mesogens align parallel with the substrate, so the long axis of the RM can interact with the substrate. One way planar alignment can be promoted is by coating the substrate with a polyimide layer, and then rubbing the alignment layer with a velvet cloth.

(197) Other suitable planar alignment layers are known in the art, like for example rubbed polyimide or alignment layers prepared by photoalignment as described in U.S. Pat. Nos. 5,602,661, 5,389,698 or 6,717,644.

(198) In general, reviews of alignment techniques are given for example by I. Sage in “Thermotropic Liquid Crystals”, edited by G. W. Gray, John Wiley & Sons, 1987, pages 75-77; and by T. Uchida and H. Seki in “Liquid Crystals—Applications and Uses Vol. 3”, edited by B. Bahadur, World Scientific Publishing, Singapore 1992, pages 1-63. A further review of alignment materials and techniques is given by J. Cognard, Mol. Cryst. Liq. Cryst. 78, Supplement 1 (1981), pages 1-77.

(199) For the production of the polymer films according to the invention, the polymerizable compounds in the polymerizable LC material are polymerized or crosslinked (if one compound contains two or more polymerizable groups) by in-situ photopolymerization.

(200) The photopolymerization can be carried out in one step. It is also possible to photopolymerize or crosslink the compounds in a second step, which have not reacted in the first step (“end curing”).

(201) In a preferred method of preparation the polymerizable LC material is coated onto a substrate and subsequently photopolymerized for example by exposure to actinic radiation as described for example in WO 01/20394, GB 2,315,072 or WO 98/04651.

(202) Photopolymerization of the LC material is preferably achieved by exposing it to actinic radiation. Actinic radiation means irradiation with light, like UV light, IR light or visible light, irradiation with X-rays or gamma rays, or irradiation with high-energy particles, such as ions or electrons. Preferably, polymerization is carried out by photo irradiation, in particular with UV light. As a source for actinic radiation, for example a single UV lamp or a set of UV lamps can be used. When using a high lamp power the curing time can be reduced. Another possible source for photo radiation is a laser, like e.g. a UV laser, an IR laser, or a visible laser. Another possible source for photo radiation is a LED lamp.

(203) The curing time is dependent, inter alia, on the reactivity of the polymerizable LC material, the thickness of the coated layer, the type of polymerization initiator and the power of the UV lamp. The curing time is preferably ≤5 minutes, very preferably ≤3 minutes, most preferably ≤1 minute. For mass production, short curing times of ≤30 seconds are preferred.

(204) A suitable UV radiation power is preferably in the range from 5 to 200 mWcm-2, more preferably in the range from 50 to 175 mWcm.sup.−2 and most preferably in the range from 100 to 150 mWcm-2.

(205) In connection with the applied UV radiation and as a function of time, a suitable UV dose is preferably in the range from 25 to 7200 mJcm.sup.−2 more preferably in the range from 100 to 7200 mJcm.sup.−2 and most preferably in the range from 200 to 7200 mJcm.sup.−2.

(206) Photopolymerization is preferably performed under an inert gas atmosphere, preferably in a heated nitrogen atmosphere, but also polymerization in air is possible.

(207) Photopolymerization is preferably performed at a temperature from 1 to 70° C., more preferably 5 to 50° C., even more preferably 15 to 30° C.

(208) The polymerized LC film according to the present invention has good adhesion to plastic substrates, in particular to TAC, COP, and colour filters. Accordingly, it can be used as adhesive or base coating for subsequent LC layers which otherwise would not well adhere to the substrates.

(209) For optical applications of the polymer film, it preferably has a thickness of from 0.5 to 10 μm, very preferably from 0.5 to 5 μm, in particular from 0.5 to 3 μm.

(210) The optical retardation (δ(λ)) of a polymer film as a function of the wavelength of the incident beam (λ) is given by the following equation (7):
δ(λ)=(2πΔn.Math.d)/λ  (7)
wherein (Δn) is the birefringence of the film, (d) is the thickness of the film and λ is the wavelength of the incident beam.

(211) According to Snellius law, the birefringence as a function of the direction of the incident beam is defined as
Δn=sin Θ/sin Ψ  (8)
wherein sin Θ is the incidence angle or the tilt angle of the optical axis in the film and sin Ψ is the corresponding reflection angle.

(212) Based on these laws, the birefringence and accordingly optical retardation depends on the thickness of a film and the tilt angle of optical axis in the film (cf. Berek's compensator). Therefore, the skilled expert is aware that different optical retardations or different birefringence can be induced by adjusting the orientation of the liquid-crystalline molecules in the polymer film.

(213) The birefringence (Δn) of the polymer film according to the present invention is preferably in the range from 0.01 to 0.4, more preferable in the range from 0.01 to 0.3 and even more preferable in the range from 0.01 to 0.25.

(214) The optical retardation as a function of the thickness of the polymer film according to the present invention is less than 200 nm, preferable less than 180 nm and even more preferable less than 150 nm.

(215) The polymer film of the present invention can also be used as alignment film or substrate for other liquid-crystalline or RM materials. The inventors have found that the polymer film obtainable from a polymerizable LC material as described above and below, is in particular useful for multilayer applications due to its improved dewetting characteristics. In this way, stacks of optical films or preferably polymerized LC films can be prepared.

(216) In summary, the polymerized LC films and polymerizable LC materials according to the present invention are useful in optical elements like polarisers, compensators, alignment layer, circular polarisers or colour filters in liquid crystal displays or projection systems, decorative images, for the preparation of liquid crystal or effect pigments, and especially in reflective films with spatially varying reflection colours, e.g. as multicolour image for decorative, information storage or security uses, such as non-forgeable documents like identity or credit cards, banknotes etc.

(217) The polymerized LC films according to the present invention can be used in displays of the transmissive or reflective type. They can be used in conventional OLED displays or LCDs, in particular LCDs.

(218) The present invention is described above and below with particular reference to the preferred embodiments. It should be understood that various changes and modifications might be made therein without departing from the spirit and scope of the invention.

(219) Many of the compounds or mixtures thereof mentioned above and below are commercially available. All of these compounds are either known or can be prepared by methods which are known per se, as described in the literature (for example in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart), to be precise under reaction conditions which are known and suitable for said reactions. Use may also be made here of variants which are known per se, but are not mentioned here.

(220) It will be appreciated that variations to the foregoing embodiments of the invention can be made while still falling within the scope of the invention. Alternative features serving the same, equivalent, or similar purpose may replace each feature disclosed in this specification, unless stated otherwise. Thus, unless stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

(221) All of the features disclosed in this specification may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. In particular, the preferred features of the invention are applicable to all aspects of the invention and may be used in any combination. Likewise, features described in non-essential combinations may be used separately (not in combination).

(222) It will be appreciated that many of the features described above, particularly of the preferred embodiments, are inventive in their own right and not just as part of an embodiment of the present invention. Independent protection may be sought for these features in addition to or alternative to any invention presently claimed.

(223) The invention will now be described in more detail by reference to the following working examples, which are illustrative only and do not limit the scope of the invention.

EXAMPLES

Example 1

(224) The following formulations are prepared in accordance with the given tables:

(225) TABLE-US-00001 Formulation 1 Surfactant 0.500% Irganox 1076 0.080% LC756 4.100% LC242 5.000% SPI-03 2.500% 2.000% 2.000% 0 2.500% 3.000% 5.080% 8.000% 15.000%  50.240%  Formulation 2 Surfactant 0.250% Irganox 1076 0.080% LC756 4.100% LC242 5.000% SPI-03 2.500% 2.000% 2.000% 2.500% 3.000% 0 5.080% 8.000% 15.000%  50.490%  Formulation 3 Surfactant 0.125% Irganox 1076 0.080% LC756 4.100% LC242 5.000% SPI-03 2.500% 2.000% 2.000% 2.500% 3.000% 5.080% 8.000% 0 15.000%  50.615%  Formulation 4 Surfactant 0.062% Irganox 1076 0.080% LC756 4.100% LC242 5.000% SPI-03 2.500% 2.000% 2.000% 2.500% 3.000% 5.080% 8.000% 15.000%  50.678% 

(226) Irganox 1076, LC756 and LC242 are commercially available from BASF, Germany; SPI-3 is commercially available from Samyang Corporation, Korea.

(227) The formulations 1 to 4 are dissolved to 20% solids in MIBK (methyl isobutyl ketone): 3-Pentanone (8:2). Each host formulation was then doped with various surfactants to create final formulations shown in the following table.

(228) Surfactant Doped Formulations in Each Host

(229) TABLE-US-00002 Formulation Surfactant 1 2 3 4 Tego Airex Formulation Formulation Formulation Formulation 901  5 17 29 41 Tego Airex Formulation Formulation Formulation Formulation 920  6 18 30 42 Tego Airex Formulation Formulation Formulation Formulation 931  7 19 31 43 Tego Airex Formulation Formulation Formulation Formulation 962  8 20 32 44 Tego Glide Formulation Formulation Formulation Formulation 435  9 21 33 45 Tego Wet Formulation Formulation Formulation Formulation 260 10 22 34 46 Tego Wet Formulation Formulation Formulation Formulation 500 11 23 35 47 Tego Wet Formulation Formulation Formulation Formulation 510 12 24 36 48 Polyfox Formulation Formulation Formulation Formulation PF-3320 13 25 37 49 Polyfox Formulation Formulation Formulation Formulation PF-7002 14 26 38 50 Polyfox Formulation Formulation Formulation Formulation PF-656 15 27 39 51 Tego Twin Formulation Formulation Formulation Formulation 4000 16 28 40 52

(230) Tego Airex 901, Tego Airex 920, Tego Airex 931, Tego Airex 962, Tego Glide 435, Tego Wet 260, Tego Wet 500, Tego Wet 510, Tego Twin 4000 are commercially available from Evonik Tego, Germany. Polyfox PF-3320 Polyfox PF-7002 Polyfox PF-656 are commercially available from Omnova Solutions Inc., USA.

(231) The formulations 5-52 are spin coated on polyimide rubbed glass at 1000 rpm for 30 s, respectively. The wet films are annealed at 60° C. for 60 s and cured in Light Hammer 6 Fusion conveyor belt UV lamp (250 mJ cm.sup.−2) under N.sub.2. Each resulting film is visually inspected for CLC alignment and visible haze by eye after initial cure. An additional coat of the same formulation was coated on top following the same method as given above. Each multiple layer coating is visually inspected for dewetting after the second annealing step.

(232) Comparative Formulations:

(233) TABLE-US-00003 Formulation Surfactant Alignment in Dewets in Alignment in No. conc. 1st Coating 2nd Coating 2nd Coating Formulation 5 0.500% ○ X X Formulation 17 0.250% ○ X X Formulation 29 0.125% ○ X X Formulation 41 0.062% ○ X X Formulation 6 0.500% ○ X X Formulation 18 0.250% ○ X X Formulation 30 0.125% ○ X X Formulation 42 0.062% ○ X X Formulation 7 0.500% X ○ X Formulation 19 0.250% X X X Formulation 31 0.125% X X X Formulation 43 0.062% ○ X X Formulation 8 0.500% X ○ Formulation 20 0.250% ○ X ○ Formulation 32 0.125% ○ ○ ○ Formulation 44 0.062% ○ ○ Formulation 9 0.500% ○ X X Formulation 21 0.250% ○ X X Formulation 33 0.125% ○ X X Formulation 45 0.062% ○ X X Formulation 10 0.500% ○ ○ X Formulation 22 0.250% ○ ○ Formulation 34 0.125% ○ ○ ○ Formulation 46 0.062% ○ ○ Formulation 11 0.500% ○ X Formulation 23 0.250% X X X Formulation 35 0.125% X X X Formulation 47 0.062% X X X Formulation 12 0.500% ○ X Formulation 24 0.250% X X X Formulation 36 0.125% X X X Formulation 48 0.062% X X X Formulation 13 0.500% ○ X X Formulation 25 0.250% ○ X X Formulation 37 0.125% ○ X X Formulation 49 0.062% ○ X X Formulation 16 0.500% ○ X X Formulation 28 0.250% ○ X X Formulation 40 0.125% ○ X Formulation 52 0.062% ○ ○
Formulations According to the Invention:

(234) TABLE-US-00004 Formulation Surfactant Alignment in Dewets in Alignment in No. conc. 1st Coating 2nd Coating 2nd Coating Formulation 15 0.500% ○ ○ X Formulation 27 0.250% ○ ○ ○ Formulation 39 0.125% ○ ○ ○ Formulation 51 0.062% ○ ○ ○ Formulation 14 0.500% ○ Formulation 26 0.250% ○ X ○ Formulation 38 0.125% ○ ○ ○ Formulation 50 0.062% ○ O=Good (Good alignment or no dewets) Δ=Bad (acceptable CLC alignment/haze or some dewets) X=(Extreme dewets)

(235) As can be seen in the above-given table, using Polyfox PF-656 (formulations 15, 27, 39, and 51) as the surfactant offers an extremely wide range of concentrations that can be used to achieve CLC alignment. This surfactant choice also has a wide range of concentrations where it does not cause dewetting of subsequent coated layers and also provides alignment to upper layers so an extra alignment layer is not required between CLC layers. Similar results could be obtained with PolyFox PF 7002 (formulations 14, 26, 38, and 50).

Example 2

(236) The following formulations are prepared in accordance with the given tables:

(237) TABLE-US-00005 Formulation 53 Polyfox 656 0.03% Irganox 1076 0.080%  SPI-03 2.500%  0 4.050%  4.500%  13.000%  75.840%  Formualtion 54 Polyfox 656 0.03% Irganox 1076 0.08% SPI-03 2.50% 3.71% 4.50% 13.00%  76.18%  Formulation 55 Polyfox 656 0.03% Irganox 1076 0.08% SPI-03 2.50% 3.38% 4.50% 0 13.00%  76.51%  Formulation 56 Polyfox 656 0.03% Irganox 1076 0.08% SPI-03 2.50% 3.04% 4.50% 13.00%  76.85%  Formulation 57 Polyfox 656 0.03% Irganox 1076 0.08% SPI-03 2.50% 2.70% 4.50% 13.00%  77.19% 

(238) Each formulation is dissolved to 20% solids in MIBK: 3-Pentanone (8:2) The formulations 53-57 are bar coated on 5× rubbed cyclic olefin polymer substrate using Mayer Bar 9 respectively. The wet films are annealed at 60° C. for 60 s and cured in Light Hammer 6 Fusion conveyor belt UV lamp (250 mJ cm.sup.−2) under N.sub.2. Each film is visually inspected for CLC alignment by eye after cure. No film crystallization or dewetting was observed for any of the coated films. Each film is measured using a Shimadzu 3600 UV-Vis spectrometer to determine the reflective wavelength and bandwidth of reflection. Film thicknesses were measured using a Dektak Profilometer. The results of these measurements are shown in the table below.

(239) TABLE-US-00006 Central Wavelength Reflection Bandwidth Film Thickness in nm in nm in μm Film 1 467 72 5.14 Film 2 504 76 5.75 Film 3 550 85 4.77 Film 4 610 96 5.38 Film 5 681 115  5.13

Example 3

(240) The following formulations are prepared in accordance with the given tables:

(241) TABLE-US-00007 Formulation 58 Polyfox 656 0.03% Irganox 1076 0.08% SPI-03 2.50% 00 4.05% 01 4.500%  02 13.00%  03 75.84%  Formulation 59 Polyfox 656 0.03% Irganox 1076 0.08% SPI-03 2.50% 04 3.04% 05 4.50% 06 13.00%  07 76.85% 

(242) The formulations are dissolved to 40% solids in MIBK: 3-Pentanone (8:2) The formulations 58 and 59 are spin coated on polyimide rubbed glass at 1000 rpm for 30 s, respectively. The wet films are annealed at 60° C. for 60 s and cured in Light Hammer 6 Fusion conveyor belt UV lamp (250 mJ cm.sup.−2) under N.sub.2.

(243) Each film is visually inspected for CLC alignment and visible haze by eye after initial cure

(244) Film 6 obtained from formulation 58 shows excellent alignment and exhibits a main Reflection Bandwidth from 425 to 510

(245) Film 7 obtained from Formulation 59 shows excellent alignment and exhibits a main Reflection Bandwidth from 550 to 675 nm.

(246) Film 8 is obtained from a multilayer coating of formulation 59 which is coated and cured as given above, followed by formulation 58 coated and cured as given above on top of the polymer film obtained from formulation 59. The multilayer film exhibits one Reflection Bandwidth from 425 to 510 nm and a second main Reflection Bandwidth from 550 to 675 nm

(247) It can be seen that using Polyfox PF656 surfactant, it is possible to coat one CLC film on top of another directly with wide bandwidths for each of the layers. There is also no detrimental effect on reflection properties of each layer as can be seen with the overlapping reflection bands.