METHOD FOR THE PREPARATION OF PHOTOALIGNING POLYMER MATERIALS AND COMPOSITIONS

Abstract

The present invention relates to a novel method for the preparation of photoaligning polymer materials comprising aryl acrylic acid ester groups, to photoalignment compositions obtained by this process, to the use of the composition as orienting layer for liquid crystals and to non-structured and structured optical elements, electro-optical elements, multi-layer systems or in nanoelectronics comprising the compositions.

Claims

1. A process for the preparation of a photoaligning polymer material comprising aryl acrylic acid ester groups comprising the steps of: a. reacting a compound of formula (II) ##STR00028## wherein: ring C is phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene, 1,4- or 2,6-naphthylene, Y is either C or O; and if Y is C then m=1 and RCOOR, wherein R is straight-chain or branched alkylene group with 1 to 20 carbon atoms which is optionally at least once substituted with halogen or with at least one siloxane moieties, or a cycloalkyl residue with 3 to 8 ring atoms which is optionally substituted with at least one halogen, alkyl or alkoxy; or if Y is 0, then m=0; with a compound of formula (III) ##STR00029## M.sup.1 signifies a repeating monomer unit from the group consisting of acrylate, methacrylate, 2-chloroacrylate, 2-phenylacrylate, acrylamide, methacrylamide, 2-chloroacrylamide, 2-phenylacrylamide, N-lower alkyl substituted acrylamide, N-lower alkyl substituted methacrylamide, N-lower alkyl substituted 2-chloroacrylamide, N-lower alkyl substituted 2-phenylacrylamide, vinyl ether, vinyl ester, styrene, diamine, amide, imide, siloxane, amic ester, and amic acid; S.sup.1 is a spacer unit; ring A signifies phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, cyclohexane-1,4-diyl, piperidine-1,4-diyl or piperazine-1,4-diyl; ring B signifies phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4- or 2,6-naphthylene, 1,3-dioxane-2,5-diyl or cyclohexane-1,4-diyl; Y.sup.1, Y.sup.2 each independently signify a single covalent bond, (CH.sub.2).sub.t, O, CO, COO, OOC, CF.sub.2O,OCF.sub.2, NR.sup.4, CONR.sup.4, R.sup.4NCO, (CH.sub.2).sub.t, O, O, O(CH.sub.2).sub.u, (CH.sub.2).sub.uNR.sup.4 or NR.sup.4(CH.sub.2).sub.u, in which R.sup.4 signifies hydrogen or lower alkyl; T signifies a whole number of 1 to 4; u signifies a whole number of 1 to 3; and m, n signifies a whole number of 0 to 4; and optionally with a compound of formula (IV) or (IV) ##STR00030## and b. optionally reacting the compound obtained under step a. with a compound of formula (V)
X(CZ.sub.qZ.sub.q)CZ.sub.rZ.sub.r(V) wherein X is OH, F, Cl or I; Z and Z are independently from each other either H or halogen; q and q are independently from each other an integer between 0 and 2; p is an integer between 0 and 10 r and r are independently from each other an integer between 0 and 3; c. polymerizing the compound obtained under step a. or b. with an organic or inorganic peroxide; d. stopping the reaction by heating.

2. The process according to claim 1, wherein the spacer unit is S.sup.2 if m and n are 0 and wherein the spacer unit is S.sup.3 if at least one of m or n is 1, and wherein S.sup.2 and S.sup.3 are unsubstituted or unsubstituted, straight-chain or branched, (CH.sub.2).sub.r, as well as (CH.sub.2).sub.rO, (CH.sub.2).sub.r,O(CH.sub.2).sub.s, (CH.sub.2).sub.rO(CH.sub.2).sub.sO, (CH.sub.2).sub.rCO, (H.sub.2).sub.rCOO, (CH.sup.2).sub.rOCO, (CH.sub.2).sub.rNR.sup.2, (CH.sub.2).sub.rCONR.sup.2, (CH.sub.2).sub.rNR.sup.2CO, (CH.sub.2).sub.rNR.sup.2COO or (CH.sub.2).sub.rNR.sup.2CONR.sup.3, which is optionally mono- or poly-substituted with C.sub.1-C.sub.24-alkyl, hydroxy, fluorine, chlorine, cyano, ether, ester, amino, amido; wherein one or more CH.sub.2group may be replaced by a linking group, alicyclic or aromatic group; and, wherein r and s are each a whole number of 1 to 20, with the proviso that 3r+s 24 for S.sup.2; and 8r+s24 for S.sup.3; and R.sup.2 and R.sup.3 each independently signify hydrogen or lower alkyl.

3. The process according to claim 1, wherein if Y=O, then the reaction with the compound of formula (IV) or (IV) takes place.

4. The process according to claim 1, wherein: M.sup.1 is a monomer unit selected from the group consisting of acrylate and methacrylate; ring A is unsubstituted phenylene or phenylene which is substituted with alkyl or alkoxy; ring B is unsubstituted phenylene or phenylene which is substituted with fluorine, alkyl or alkoxy; Y.sup.1, Y.sup.2 each independently is a single covalent bond, COO, OOC; m, n each independently is 0 or 1; ring C is unsubstituted phenylene or phenylene which is substituted with alkyl or alkoxy; S.sup.1 is a spacer unit, wherein, if m and n are 0 then the spacer unit is S.sup.2 and if at least one m or n is 1, then the spacer unit is S.sup.3; wherein S.sup.2 is C.sub.4-C.sub.24 alkylene; wherein S.sup.3 is C.sub.6-C.sub.24 alkylene; wherein alkylene is unsubstituted or substituted, straight-chain or branched alkylene, in which one or more CH.sub.2 groups may be replaced by at least one linking group, alicyclic or/and aromatic group; and wherein Z is O.

5. Compounds obtained by the process according to claim 1.

6. A composition comprising the compounds according to claim5.

7. A composition comprising: a homopolymer comprising monomers of formula (I): ##STR00031## and at least one monomer of formula (I); wherein M.sup.1, S.sup.1, ring A, Y.sup.1, ring B, Y.sup.2, n, m and ring C have the same meaning as described above; and wherein Z signifies O or NR.sup.5, in which R.sup.5 signifies hydrogen or lower alkyl, or a second group of formula D or D; and wherein D signifies a straight-chain or branched alkylene group with 1 to 20 carbon atoms which is optionally at least once substituted with halogen or with at least one siloxane moieties, or a cycloalkyl residue with 3 to 8 ring atoms which is optionally substituted with at least one halogen, alkyl or alkoxy.

8. The composition according to claim 7, wherein: M.sup.1 is a monomer unit selected from the group consisting of acrylate and methacrylate; ring A is unsubstituted phenylene or phenylene which is substituted with alkyl or alkoxy; ring B is unsubstituted phenylene or phenylene which is substituted with fluorine, alkyl or alkoxy; Y.sup.1, Y.sup.2 each independently is a single covalent bond, COO, OOC; m, n each independently is 0 or 1; ring C is unsubstituted phenylene or phenylene which is substituted with alkyl or alkoxy; and S.sup.i is a spacer unit, wherein, if m and n are 0 then the spacer unit is S.sup.2 and if at least one m or n is 1, then the spacer unit is S.sup.3; wherein S.sup.2 is C.sub.4-C.sub.24alkylene; wherein S.sup.3 is C.sub.8-C24alkylene; wherein alkylene is unsubstituted or substituted, straight-chain or branched alkylene, in which one or more CH.sub.2 groups may be replaced by at least one linking group, alicyclic or/and aromatic group; and wherein Z is O.

9. The composition according to claim 7 further comprising a solvent and optionally at least an additive.

10. The composition according to claim 9, wherein the at least one additive is selected from the group consisting of polymerizable liquid crystal, UV curable compounds, crosslinking agents, silane-containing compounds, photo-active additives, photo-initiators, surfactats, emulsifiers, antioxidant, levelling agent, dyes, epoxy-containing crosslinking agents and curable compounds.

11. A method of using the composition according to claim 7 comprising using the composition as an orienting layer for liquid crystals.

12. A method for the preparation of an orientation layer for liquid crystals comprising irradiating the composition according to claim 7 with aligning light.

13. Orientation layers comprising a composition according to claim 7.

14. Optical, electro-optical or nanoeletronic elements comprising a composition according to claim 7.

15. Optical, electro-optical or nanoeletronic elements comprising a composition comprising an orientation layer according to claim 14.

16. The process according to claim 2, wherein if Y=O, then the reaction with the compound of formula (IV) or (IV) takes place.

17. The process according to claim 2, wherein: M.sup.1 is a monomer unit selected from the group consisting of acrylate and methacrylate; ring A is unsubstituted phenylene or phenylene which is substituted with alkyl or alkoxy; ring B is unsubstituted phenylene or phenylene which is substituted with fluorine, alkyl or alkoxy; Y.sup.1, Y.sup.2 each independently is a single covalent bond, COO, OOC; m, n each independently is 0 or 1; ring C is unsubstituted phenylene or phenylene which is substituted with alkyl or alkoxy; S.sup.1 is a spacer unit, wherein, if m and n are 0 then the spacer unit is S.sup.2 and if at least one m or n is 1, then the spacer unit is S.sup.3; wherein S.sup.2 is C.sub.4-C.sub.24 alkylene; wherein S.sup.3 is C.sub.6-C.sub.24 alkylene; wherein alkylene is unsubstituted or substituted, straight-chain or branched alkylene, in which one or more CH.sub.2 groups may be replaced by at least one linking group, alicyclic or/and aromatic group; and wherein Z is O.

18. The composition according to claim 8 further comprising a solvent and optionally at least an additive.

19. The composition according to claim 18, wherein the at least one additive is selected from the group consisting of polymerizable liquid crystal, UV curable compounds, crosslinking agents, silane-containing compounds, photo-active additives, photo-initiators, surfactats, emulsifiers, antioxidant, levelling agent, dyes, epoxy-containing crosslinking agents and curable compounds.

Description

EXAMPLES

Example 1

Preparation of (E)-3-[4-[6-(2-methylprop-2-enoyloxy)hexoxy]phenyl]prop-2-enoic acid

[0147] ##STR00012##

[0148] 100.0 g of 4-hydroxybenzaldehyde, 147.0 g of potassium carbonate (powder), 12.0 g of potassium iodide and 0.1 g of phenothiazine are suspended in 500.0 g of DMF. To this suspension is added 176.0 g of 6-chlorohexyl 2-methylprop-2-enoate. The resulting mixture is then heated up to 90 C. under Nitrogen atmosphere. After 6 hours at 90 C. the reaction mixture is cooled down to 20 C. and filtered on Hyflo. The remaining solid is washed with 100 g of DMF. The resulting DMF solution is transferred in a reactor. To this solution 14.3 g of morpholine and 0.1 g of phenothiazine are added. The reaction mixture is then heated up to 85 C. and a solution of 170.7 g of malonic acid in 270 g of DMF is added dropwise over a period of 4 hours. After 4 more hours of stirring at this temperature the reaction mixture is cooled to 60 C. and 300 mL of water are added dropwise. After cooling down the mixture to 15 C. the solid is filtered off to obtain 218 g of Compound 1 as a yellowish solid with an HPLC purity of >95%.

[0149] 1H NMR (300 MHz) in DMSO-d6 of compound 1: 12.05; (s, 1 H), 7.61; (d, 2H), 7.49; (d, 1 H), 6.94; (d, 2H), 6.35; (d, 1H), 6.01; (t, 1H), 5.65; (t, 1H), 4.09; (t, 2H), 4.00; (t, 2H), 1.87; (m, 3H), 1.72; (m, 2H), 1.63; (m, 2H), 1.41; (m, 4H).

Example 2

Preparation of 6-[4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]hexyl 2-methylprop-2-enoate

[0150] ##STR00013##

[0151] To 28 g of Compound 1 obtained according to Example 1 in 150m1 of acetone are added 0.05 g of BHT, 0.05g of phenothiazine and 16.4 g of 1,1-carbonyldiimidazole (CDI). The reaction mixture is stirred for 1 hour at room temperature (RT). Then, 12.7 g of 2,2,2-trifluoroethanol, 1.0 g of DMAP and 13.0 g of trimethylamine are added to the solution and stirred for 3 more hours at RT. The reaction mixture is then filtered over Hyflo, the remaining solid is washed with 50g of acetone. The filtered solution is cooled down to 10 C. and 250 g of water are then added dropwise for 1 hour, forming a precipitate which is stirred in solution for another 1 hour. After filtration and washing 25 g of Compound 2 is obtained as a white solid with an HPLC purity of >97%.

[0152] 1H NMR (300 MHz) in CDCl3 of compound 2: 7.75; (d, 1H), 7.51; (d, 2H), 6.91; (d, 2H), 6.35; (d, 1H), 6.11; (m, 1H), 5.56; (m, 1H), 4.60; (dd, 2H), 4.18; (t, 2H), 4.02; (t, 2H), 1.96; (m, 3H), 1.84; (m, 2H), 1.74; (m, 2H), 1.51; (m, 4H).

Alternative synthesis of Compound 2

[0153] 400.1 g of 4-hydroxybenzaldehyde, 588.4 g of potassium carbonate (powder), 40.0 g of potassium iodide and 0.4 g of phenothiazine are suspended in 1600 g of DMF. To this suspension is added 710.7 g of 6-chlorohexyl 2-methylprop-2-enoate. The resulting mixture is then heated up to 85 C. under Nitrogen atmosphere. After 18 hours at 85 C. the reaction mixture is cooled down to 20 C. and filtered over Hyflo. The remaining solid is washed with 400 g of DMF. The resulting DMF solution is transferred in a reactor.

[0154] To this solution 0.6 g of phenothiazine, 0.6 g pf BHT, 727.98 g of propanedioic acid, 1-(2,2,2-trifluoroethyl) ester (obtained from the condensation of 2,2,2-trifluoroethanol and Meldrum's acid) in 250 g of DMF and 114 g of morpholine are added. The reaction mixture is then stirred under nitrogen at 50 C. After 6 hours the reaction is cooled down to RT, and then isopropanol was added. Water is then added dropwise to precipitate the product out of the orange solution. After filtration and washing 1080 g of Compound 2 is obtained as a white solid with an HPLC purity of >97%.

Example 3

Preparation of 6-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]hexyl 2-methylprop-2-enoate

[0155] ##STR00014##

[0156] Following the alternative synthesis method described above, the condensation of 6-chlorohexyl 2-methylprop-2-enoate with Vanillin, followed by the condensation with propanedioic acid, 1-(2,2,2-trifluoroethyl) ester lead to Compound 3 in 78% yield with an HPLC purity of >97%.

[0157] 1H NMR (300 MHz) in DMSO-d6 of Compound 3: 7.70; (d, 1 H), 7.42; (d, 1H), 7.26; (d, 1H), 6.98; (d, 1H), 6.68; (d, 1H), 6.02; (m, 1H), 5.66; (m, 1H), 4.85; (dd, 2H), 4.10; (t, 2H), 4.03; (t, 2H), 3.81; (s, 3H), 1.88; (m, 3H), 1.72; (m, 2H), 1.64; (m, 2H), 1.43; (m, 4H).

Example 4

Preparation of 8-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]octyl 2-methylprop-2-enoate

[0158] ##STR00015##

[0159] As described for Compound 3, the condensation of 8-chlorooctyl 2-methylprop-2-enoate with 4-hydroxybenzaldehyde, followed by the condensation with propanedioic acid, 1-(2,2,2-trifluoroethyl) ester lead to Compound 4 in 70% yield with an HPLC purity of >97%.

[0160] 1H NMR (300MHz) in CDCI3 of Compound 4: 7.73; (d, 1 H), 7.47; (d, 2H), 6.91; (d, 2H), 6.35; (d, 1H), 6.09; (m, 1H), 5.56; (m, 1H), 4.57; (dd, 2H), 4.14; (t, 2H), 3.98; (t, 2H), 1.94; (m, 3H), 1.77; (m, 2H), 1.68; (m, 2H), 1.45; (m, 8H).

Example 5

Preparation of 8-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]octyl 2-methylprop-2-enoate

[0161] ##STR00016##

[0162] As described for Compound 3, the condensation of 8-chlorooctyl 2-methylprop-2-enoate with Vanillin, followed by the condensation with propanedioic acid, 1-(2,2,2-trifluoroethyl) ester lead to Compound 5 in 60% yield with an HPLC purity of >95%.

[0163] 1H NMR (300 MHz) in DMSO-d6 of Compound 5: 7.70; (d, 1 H), 7.42; (d, 1H), 7.30; (d, 1H), 7.00; (d, 1H), 6.70; (d, 1H), 6.01; (m, 1H), 5.66; (m, 1H), 4.85; (dd, 2H), 4.10; (t, 2H), 3.99; (t, 2H), 3.80; (s, 3H), 1.87; (m, 3H), 1.72; (m, 2H), 1.61; (m, 2H), 1.33; (m, 8H).

Example 6

Preparation of [2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenyl] 4-(6-prop-2-enoyloxyhexoxy)benzoate

[0164] ##STR00017##

[0165] As described for Compound 3, the condensation of 8-chlorooctyl 2-methylprop-2-enoate with (4-formyl-2-methoxy-phenyl) 4-hydroxybenzoate, followed by the condensation with propanedioic acid, 1-(2,2,2-trifluoroethyl) ester lead to Compound 6 in 76% yield with an HPLC purity of >93%.

[0166] 1H NMR (300MHz) in DMSO-d6 of Compound 6: 8.06; (d, 2H), 7.83; (d, 1H), 7.78; (s, 1H), 7.40; (d, 1 H), 7.30; (d, 1H), 7.11; (d, 2H), 6.90; (d, 1H), 6.30 (d, 1 H), 6.20 (dd, 1 H), 5.95; (d, 1H), 4.90; (dd, 2H), 4.10; (m, 4H), 3.83; (s, 3H), 1.77; (m, 2H), 1.65; (m, 2H), 1.44; (m, 4H).

Example 7

Preparation of 6-[4-[(E)-3-oxo-3-(4,4,4-trifluorobutoxy)prop-1-enyl]phenoxy]hexyl 2-methylprop-2-enoate

[0167] ##STR00018##

[0168] The Compound 7 is obtained by reacting compound 1 with 1,1,1-trifluoro-4-iodo-butane using the same protocol as described in Example 2. Compound 7 is obtained quantitatively as a white solid with an HPLC purity >97%.

Example 8

Preparation of 6-[4-[(E)-3-methoxy-3-oxo-prop-1-enyl]phenoxy]hexyl 2-methylprop-2-enoate

[0169] ##STR00019##

[0170] The Compound 8 is obtained by similar method as described for Example 1 by reatcing methyl (E)-3-(4-hydroxyphenyl)prop-2-enoate with 6-chlorohexyl 2-methylprop-2-enoate. Compound 8 is obtained quantitatively as a white solid with an HPLC purity >97%.

Examples 9-15

Polymerization Process

[0171] 25 g of monomeric compound as synthesized in Example 2 to 8 are mixed together with 94 g of cyclohexanone (CHN) and stirred under Nitrogen until complete dissolution. The reaction mixture is then heated up to 75 C. and then 0.4 g of Luperox LP (Lauryl peroxide) are added in one portion. The reaction mixture is then maintained at 75 C. for 5 hours then the temperature is increased to 100 C. After 1 hour at 100 C. the reaction mixture is cooled down to RT and then filtered to obtain quantitatively the polymer in CHN solution. The resulting polymer solution obtained is called Photoalignment Composition.

Example 9

Preparation of Poly-6-[4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]hexyl 2,2-dimethylbutanoate Polymer 1

[0172] ##STR00020##

[0173] Following the polymerization process described above the Photoalignment Composition 1 is obtained, containing the polymer 1 (Mw=151000 and Mn=41800) and its monomeric compound 2 in a ratio 90.6%:9.4% (measured by GPC).

Example 10

Preparation of Poly-6-[4-[(E)-3-oxo-3-(4,4,4-trifluorobutoxy)prop-1-enyl]phenoxy]hexyl 2,2-dimethylbutanoate Polymer 2

[0174] ##STR00021##

[0175] Following the polymerization process described above the Photoalignment Composition 2 is obtained, containing the polymer 2 (Mw=138000 and Mn=44600) and its monomeric compound 7 in a ratio 90.5%:9.5% (measured by GPC).

Example 11

Preparation of Poly- 6-[4-[(E)-3-methoxy-3-oxo-prop-1-enyl]phenoxy]hexyl 2-methylprop-2-enoate Polymer 3.

[0176] ##STR00022##

[0177] Following the polymerization process described above the Photoalignment Composition 3 is obtained, containing the polymer 3 (Mw=176700 and Mn =39900) and its monomeric compound 8 in a ratio 91.8%:8.2% (measured by GPC).

Example 12

Preparation of Poly-6-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]hexyl 2-methylprop-2-enoate Polymer 4

[0178] ##STR00023##

[0179] Following the polymerization process described above the Photoalignment Composition 4 is obtained, containing the polymer 4 (Mw=160700 and Mn=59500) and its monomeric compound 3 in a ratio 90.7%:9.3% (measured by GPC).

Example 13

Preparation of Poly-8-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]octyl 2-methylprop-2-enoate Polymer 5

[0180] ##STR00024##

[0181] Following the polymerization process described above the Photoalignment Composition 5 is obtained, containing the polymer 5 (Mw=131600 and Mn=53200) and its monomeric compound 4 in a ratio 89.4%:10.6% (measured by GPC).

Example 14

Preparation of Poly-8-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenoxy]octyl 2-methylprop-2-enoate Polymer 6

[0182] ##STR00025##

[0183] Following the polymerization process described above the Photoalignment Composition 6 is obtained, containing the polymer 6 (Mw=212100 and Mn=66100) and its monomeric compound 5 in a ratio 92.3%:7.7% (measured by GPC).

Example 15

Preparation of Poly-[2-methoxy-4-[(E)-3-oxo-3-(2,2,2-trifluoroethoxy)prop-1-enyl]phenyl]4-(6-prop-2-enoyloxyhexoxy)benzoate Polymer 7

[0184] ##STR00026##

[0185] Following the polymerization process described above the Photoalignment Composition 7 is obtained, containing the polymer 7 (Mw=228000 and Mn=32900) and its monomeric compound 6 in a ratio 99.1%:0.9% (measured by GPC).

Examples 16-22

Preparation of Photoalignment Solutions

Example 16

Preparation of PAS1

[0186] The solution PAS1 is prepared by adding 15 wt % of the Photoalignment Composition 1 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

Example 17

Preparation of PAS2

[0187] The solution PAS2 is prepared by adding 15 wt % of the Photoalignment Composition 2 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

Example 18

Preparation of PAS3

[0188] The solution PAS3 is prepared by adding 15 wt % of the Photoalignment Composition 3 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

Example 19

Preparation of PAS4

[0189] The solution PAS4 is prepared by adding 15 wt % of the Photoalignment Composition 4 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

Example 20

Preparation of PAS6

[0190] The solution PAS4 is prepared by adding 15 wt % of the Photoalignment Composition 5 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

Example 21

Preparation of PAS6

[0191] The solution PAS6 is prepared by adding 15 wt % of the Photoalignment Composition 6 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

Example 22

Preparation of PAS7

[0192] The solution PAS7 is prepared by adding 15 wt % of the Photoalignment Composition 7 in 85 wt % of methoxypropylacetate and stirring the mixture for 30 minutes at room temperature.

APPLICATION EXAMPLES

Example 23: Preparation of a Primer Coated Substrate

[0193] A triacetate cellulose (TAC) foil was coated by means of Kbar coater (bar size 1) with a primer solution (DYMAX OC-4021 20 w % solid content in 80% Butyl acetate). The wet film was dried at 80 C. for 30 s; the thickness of the resulting dry film was about 2 m. Then the dry film was exposed to UV light (1500 mJ, under nitrogen atmosphere).

Example 24: Preparation of an orientation layer using Photoalignment Solutions (PAS)

[0194] A primer coated TAC substrate of example 23 was Kbar coated (bar size 0) with a Photoalignment Solution (PAS). The wet film was dried at 80 C. for 30 s; the dry film thickness was about 100 nm. Then the dry film was exposed to aligning light, which was collimated and linearly polarized UV (LPUV) light (280-320 nm) with various exposure energy from 10 to 100 mJ/cm2. The plane of polarization was 0 with regard to a reference edge on the TAC substrate.

Example 25: Preparation of an LCP Layer Aligned by the Orientation Layer

[0195] A solution S-LCC1 is prepared by dissolving 35 wt % of

TABLE-US-00001 98.525% LCC1 1.00% Irgacure 907 (BASF) 0.20% Tinuvin 123 (BASF) 0.25 Tegoflow 300 (Evonik) 0.025% BHT (Sigma Aldrich)
in 65 wt % of a solvent mixture of 80% n-butylacetate and 20% Cyclohexanone and stirring the mixture for 30 minutes at room temperature.

LCC1 has the Following Structure

[0196] pentyl 2,5-bis[[4-(6-prop-2-enoyloxyhexoxy)benzoyl]oxy]benzoate

##STR00027##

[0197] An LCP layer is prepared on top of the orientation layer of example 24 by Kbar coating (bar size 1) the LCP solution S-LCC1. The wet layer was dried at 50 C. for 60s and subsequently the liquid crystals are cross-linked at room temperature under nitrogen atmosphere by UV-A light exposure of 30 mW/cm2 for 50 seconds.

Evaluation of Orientation

[0198] For an efficient manufacturing process it is of interest to know how much exposure energy does a photo-alignment layer require to achieve a good visible and homogeneous (without any visible defect) contrast in a LCP layer aligned by the orientation layer. The films produced have been analysed between crossed polarizers.

[0199] Alignment quality has been ranked as the following: [0200] .box-tangle-solidup..box-tangle-solidup. very good alignment homogeneous orientation [0201] .box-tangle-solidup. good orientation (disclination lines (DL's) area <1% of coating area) [0202] few DL's (15% of coating area) [0203] x DL's visible (>5% of coating area) [0204] xx inhomogeneous orientation or no orientation

Results

[0205] Optical devices have been produced by the following sequence, a primer coated substrate (as produced in Example 23) has been coated by an orientation layer using PAM materials (as described in Example 24) and aligning an LCP layer (as shown in Example 25). Various exposure energies have been used to orient the PAM materials. Summary of the results are shown in the Table below:

TABLE-US-00002 TABLE 1 LPUV dosage (mJ/cm.sup.2) 10 20 30 40 50 60 70 80 90 100 150 200 250 PAS1 XX XX X .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. PAS2 XX XX XX XX XX XX XX X X X PAS3 XX .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. PAS4 XX X X .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. PAS5 XX X .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. PAS6 XX XX XX X X .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. PAS7 XX XX X X .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup. .box-tangle-solidup..box-tangle-solidup.