Regioselectively substituted cellulose ester based C+ compensation films with improved wavelength dispersion

A film, comprising:

• (1) a regioselectively substituted cellulose ester comprising:
• (i) a plurality of aromatic-CO— substituents;
• (ii) a plurality of a first unsaturated or saturated (C1-6) alkyl-CO— substituents;
• and
• (iii) a plurality of hydroxyl substituents;
• wherein:
• the degree of substitution for the hydroxyl (“DSOH”) is from 0 to 0.7,
• the degree of substitution for the aromatic-CO-substituent (“DSArco”) is from 0.8 to 1.6,
• the degree of substitution for the (C1-6)alkyl-CO— substituent (“DSAK”) is from 0.9-2.2, and
• the plurality of aromatic-CO-— is an (C6-20) aryl-CO—, wherein the aryl is unsubstituted or substituted by 1-5 R1;
• and
• (2) a component A that is
• wherein:
• ring A is an (C6-20)aryl or a 5 to 10-membered heteroaryl containing 1-4 heteroatoms selected from the group consisting of N, O, and S;
• ring B is (C6-20)aryl or 5 to 10 membered heteroaryl containing 1-4 heteroatoms selected from the group consisting of N, O, and S;
• ring C is (C6-20)aryl;
• or 5 to 10 membered heteroaryl containing 1-4 heteroatoms selected from the group consisting of N, O, and S;
• R1 is alkyl, haloalkyl, (C6-20)aryl optionally by 1-5 substituted by alkyl, haloalkyl, alkoxy, haloalkoxy, halo;
• 5 to 10-membered heteroaryl containing 1-4 heteroatoms selected from the group consisting of N, O, and S;
• —CH2C(O)—R3;
• R2 is independently hydrogen, alkyl, or haloalkyl;
• R3 is alkyl, haloalkyl, (C6-20)aryl, or 5 to 10-membered heteroaryl containing 1-4 heteroatoms selected from the group consisting of N, O, and S, wherein the aryl or heteroaryl are unsubstituted or substituted by 1-5 R6;
• R4 is (C1-20) alkyl, halo (C1-20) alkyl, (C1-20)alkyl-CO—(C1-20)alkyl,
• wherein each is unsubstituted or substituted by 1-3 hydroxyl, (C1-20)alkoxyl, or halo (C1-20)alkoxyl. hydroxy(C1-20)alkyl, (C1-20)alkoxy-(C1-20)alkyl, (C1-20)alkoxy -hydroxy (C1-20)alkyl, or (C1-20)alkoxy-(C1-20)alkyl—CO—(C1-20)alkyl-;
• each R5 is independently hydroxy, cyano, alkyl, haloalkyl, alkoxy, haloalkoxy, or halo;
• each R6 is independently hydroxy, cyano, alkyl, haloalkyl, alkoxy, haloalkoxy, or halo or (C6-20)aryl, wherein the aryl is unsubstituted or substituted by 1-5 R7;
• each R7 is independently hydroxyl, (C1-6)alkyl, halo(C1-6)alkyl, or (C1-6)alkoxyl;
• R8 is R4—O—, (C1-20)alkyl, halo(C1-20)alkyl, (C1-20)alkyl-CO—(C1-20)alkyl-, (C1-20)alkenyl, (C1-20)alkenyl-O—, (C1-20)alkyl-COO—(C1-20)alkyl-, (C1-20)alkyl—COO—, (C1-20)alkyl, wherein 1-2 carbon atoms are replaced by O, N, or S, (C6-10) aryl, 5- to 10-membered heteroaryl containing 1-4 heteroatoms selected from the group consisting of N, O, and S,
• wherein each of the groups are unsubstituted or substituted by 1-3 hydroxyl, (C1-20) alkoxyl, or halo(C1-20)alkoxyl. hydroxy(C1-20)alkyl, (C1-20)alkoxy—(C1-20)alkyl, (C1-20)alkoxy-hydroxy(C1-20)alkyl, or (C1-20)alkoxy-(C1-20)alkyl-CO—(C1-20)alkyl-;
• each m is 1, 2, 3, 4 or 5;
• n is 1, 2, 3, 4, or 5,
• wherein:
• the component A is present from 1 wt % to 30 wt %, based on the total weight of the composition,
• the thickness of the film (“d”) in microns is from 1 μm to 200 μm,
• the film exhibits a Re (589 nm) that is in the range of −10 nm to 10 nm,
• the ratio of the Rth (589 nm) and d (nm) multiplied by 103 is greater than 1.0,
• the Re l (589 nm) is the in-plane retardation measured at 589 nm,
• the Rth(589 nm) is the out-of-plane retardation measured at 589 nm.