Patent ID: 7105586

Claim:
A polymerizable mixture comprising: a1) 10 to 99% by weight of at least one compound according to formula I having one polymerizable functional group, a2) 5 to 70% by weight of at least one compound according to formula I having two or more polymerizable functional groups, and b) 0.01 to 5% by weight of an initiator; wherein the at least one compound of formula I which has one polymerizable group is: P-(Sp-X) n -MG-R I wherein P is a polymerizable group, Sp is a linear alkylene group having 1 to 20 C atoms, optionally one or more non-adjacent CH 2 groups may be replaced by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —O—CO—, —S—CO—, —O—COO—, —CO—S—, —CO—O—, —CH(halogen)-, —CH(CN)—, —CH═CH—or —C≡C—, X is a group of—O—, —S—, —CO—, —COO—, —OCO—, —OCOO— or a single bond, n is 0 or 1, MG is a mesogenic group, and R is an alkyl radical with up to 25 C atoms optionally unsubstituted, mono- or polysubstituted by halogen or CN, optionally one or more non-adjacent CH 2 groups are replaced, independently, by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—or —C≡C— where oxygen atoms are not linked directly to one another, or R is halogen or cyano; wherein the at least one compound which has two or more polymerizable groups of formula I is: P-(Sp-X) n -MG-R I wherein P is a polymerizable group, Sp is a linear alkylene group having 1 to 20 C atoms, optionally one or more non-adjacent CH 2 groups may be replaced by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —O—CO—, —S—CO—, —O—COO—, —CO—S—, —CO—O—, —CH(halogen)-, —CH(CN)—, —CH═CH—or —C≡C—, X is a group of —O—, —S—, —CO—, —COO—, —OCO—, —OCOO—or a single bond, n is 0 or 1, MG is a mesogenic group, and R is, independently, P-(Sp-X) n — and wherein the mixture does not contain a chiral compound.