摘要:
The invention relates to a linear UV polarizer based on a polymerized mesogen obtained by curing with actinic radiation or heat of a polymerizable composition comprising:a) a liquid crystalline component A composed of one or more achiral mesogenic compounds having at least one polymerizable end group optionally linked via a spacer group to a mesogenic core,b) a dichroic component B that absorbs light in the UV region, with an absorption maximum of from 320 to 440 nm, andc) a photoinitiator or thermal initiator component C.
摘要:
An electrooptical system is disclosed in which a PDLC film is positioned between 2 electrode layers. The PDLC film contains a liquid crystal mixture forming microdroplets in an optically isotropic, transparent polymer matrix. The liquid crystal mixture comprises one or more compounds of formula I ##STR1## wherein R, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2, X.sup.1, X.sup.2, Q, Y and n as herein defined, and one or more reactive liquid crystalline compounds. The PDLC film exhibits improved switching times, especially at low temperatures.
摘要:
An electrooptical systemwhich between 2 electrode layers contains a PDLC film comprising a liquid crystal mixture forming microdroplets in an optically isotropic, transparent polymer matrix,in which one of the refractive indices of the liquid crystal mixture is matched to the refractive index of the polymer matrix, andwhich in one of the two switching states has reduced transmission compared with the other state independent of the polarization of the incident light,characterized in that the precursor of the PDLC film comprisesa) 50-90 wt. % of a liquid crystal mixture containing one or more compounds of the formula I ##STR1## b) 15-49.5 wt. % of the precursor of the polymer matrix.
摘要:
An electrooptical system is disclosed in which a PDLC film is positioned between 2 electrode layers. The PDLC film contains a liquid crystal mixture forming microdroplets in an optically isotropic, transparent polymer matrix. The liquid crystal mixture comprises one or more compounds of formula I ##STR1## wherein R, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2, X.sup.1, X.sup.2, Q, Y and n are as herein defined, and one or more reactive liquid crystalline compounds. The PDLC film exhibits improved switching times, especially at low temperatures.
摘要:
An electrooptical system is disclosed in which a PDLC film is positioned between 2 electrode layers. The PDLC film contains a liquid crystal mixture forming microdroplets in an optically isotropic, transparent polymer matrix. The liquid crystal mixture comprises one or more compounds of formula I ##STR1## wherein R, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2, X.sup.1, X.sup.2, Q, Y and n are as herein defined, and one or more reactive liquid crystalline compounds. The PDLC film exhibits improved switching times, especially at low temperatures.
摘要:
To improve switching times, especially at low temperatures, one or more reactive liquid crystalline compounds is added to a liquid crystal mixture used in an electrooptical system. The electrooptical system comprises a PDLC film comprising a liquid crystal mixture forming micro- droplets in an optically isotropic, transparent polymer matrix between 2 electrode layers. The reactive liquid crystalline compounds are of formula II, R′—G′—R″, wherein R′, G′ and R″ are as defined herein. The liquid crystal mixture comprises one or more compounds of the formula I wherein R, A1, A2, Z1, Z2, X1, X2, Q, Y and n are as defined herein.
摘要:
An electroptical system which between 2 electrode layers contains a PDLC film comprising a liquid crystal mixture forming micro-droplets in an optically isotropic, transparent polymer matrix, in which one of the refractive indices of the liquid crystal mixture is matched to the refractive index of the polymer matrix, which exhibits an electrically switchable transparency essentially independent of the polarization of the incident light, the precursor of the PDLC film of which comprises one or more monomers, oligomers and/or prepolymers and a photoinitiator, and is cured photoradically, the liquid crystal mixture of which comprises one or more compounds of the formula I in which the substituents are defined herein characterized in that the liquid crystal mixture additionally contains one or more reactive liquid crystalline compounds in order to obtain improved switching times especially at low temperatures.
摘要:
The invention relates to an electrooptical liquid crystal systemwhich contains a dual frequency liquid crystal mixture and a further optically transparent polymeric medium between two electrode layers which optionally may be attached to substrates,in which the ordinary refractive index of the liquid crystal mixture essentially agrees with the refractive index of the polymeric medium n.sub.m and/or in which the quotient of the mass of the liquid crystal mixture and of the mass of the polymeric medium is 1.5 or more,which has a reduced transmission in the on-state compared to the off-state, andwhich is obtained by polymerization of a composition containing the dual frequency liquid crystal mixture and a precursor of the polymeric medium,characterized in that an electrical field is applied during the curing process which exhibits a frequency below the cross-over frequency of the dual frequency liquid crystal mixture so that the molecules of the dual frequency liquid crystal mixture are aligned essentially into the direction of the electrical field.
摘要:
An electrooptical system containing a PDLC film is disclosed. The precursor of the PDLC film comprises(a) 30-85 wt. % of a liquid crystal mixture containing one or more compounds of the formula I ##STR1## wherein R, Z.sup.1, Z.sup.2, A.sup.1, A.sup.2, X.sup.2, X.sup.2, Q, n and Y are as defined herein,(b) 15-68 wt. % of the precursor of the polymer matrix at least comprisinga component A containing at least 5 wt. % of one or more at least difunctional thiol monomers and/or oligomers,a component B containing at least 10 wt. % of one or more at least difunctional monomers and/or oligomers of the ene type,a component C containing at least 3 wt. % of one or more monofunctional monomers and/or oligomers of the ene type with a molar mass of less than 250 g/mol,optionally a component D containing polymerizable compounds other than ene-type or thiol-type compounds; and(c) 0.1-5 wt. % of a radical photoinitiator, with the mass ratios given under (a), (b) and (c) being related to the mass of the precursor of the PDLC film and the mass ratios of the components A, B and C relating to the mass of the precursor of the polymer matrix.
摘要:
The invention relates to an electroptical system which, between 2 electrode layers, contains a PDLC film comprising a liquid crystal mixture forming micro-droplets in an optically isotropic, transparent polymer matrix. The liquid crystal mixture comprises one or more compounds of the formula I ##STR1## wherein Z.sup.1, Z.sup.2, ##STR2## X.sup.1, X.sup.2, Q, Y, n and R are as defined herein. The liquid crystal mixture additionally contains one or more reactive liquid crystalline compounds in order to obtain improved switching times especially at low temperatures.