Liquid crystal droplets dispersed in thin films of UV-curable polymers

Claim 1

An optically responsive film comprising birefringent nematic and/or brirefringent chiral nematic liquid crystal microdroplets dispersed in a film of the ultraviolet radiation cured reaction product of a polyallyl compound and a polythiol taken from the group consisting of Z[OCO(CH 2 ) n SH] m , where Z=a polyvalent organic moiety which is the CH 0-3 group containing nucleus of a tri- or tetravalent alcohol of the type of glycerol or pentaerythritol, m=3 or 4and n=1 to 5, said microdroplets displaying positive dielectric anisotropy and/or positive diamagnetic anisotropy, said film being capable of undergoing repeated thermally and electrically or magnetically induced transitions between opaque and transparent.

Claim 5

A method of making an optically responsive film containing microdroplets of a birefringent nematic and/or birefringent chiral nematic liquid crystal material dispersed in a polymer film comprising mixing a liquid crystal material with the UV-curable liquid precursor mixture comprising a polyallyl compound and a polythiol taken from the group consisting of Z[OCO(CH 2 ) n SH] m , where Z=a polyvalent organic moiety which is the CH 0-3 group containing nucleus of a tri- or tetravalent alcohol of the type of glycerol or pentaerythritol, m=3 or 4and n=1 to 5, and thereafter curing the mixture in the form of a film with high intensity ultraviolet radiation to thereby form a cured polymer matrix which is a reaction product of said allyl compound and polythiol containing dispersed therein droplets of liquid crystal material displaying positive dielectric anisotropy and/or positive diamagnetic anisotropy.

Claim 6

A method of making an optically responsive film containing microdroplets of a birefringent nematic and/or birefringent chiral nematic liquid crystal material dispersed in a polymer film comprising mixing a liquid crystal material with the UV-curable liquid precursor mixture comprising a polyallyl compound and a polythiol taken from the group consisting of Z[OCO(CH 2 ) n SH] m , where Z=a polyvalent organic moiety which is the CH 0-3 group containing nucleus of a tri- or tetravalent alcohol of the type of glycerol or pentaerythritol, m=3 or 4and n=1 to 5, and thereafter curing the mixture in the form of a film with high intensity ultraviolet radiation to thereby form a cured polymer matrix which is a reaction product of said allyl compound and polythiol containing dispersed therein droplets of liquid crystal material displaying positive dielectric anisotropy and/or positive diamagnetic anisotropy.

Claim 7

A method of making an optically responsive film containing microdroplets of a birefringent nematic and/or birefringent chiral nematic liquid crystal material dispersed in a polymer film comprising mixing a liquid crystal material with the UV-curable liquid precursor mixture comprising triallyl isocyanurate and pentaerythritol tetrakis(3-mercapto-propionate) and thereafter curing the mixture in the form of a film with high intensity ultraviolet radiation to thereby form a cured polymer matrix which is a reaction product of said precursors containing dispersed therein droplets of liquid crystal material displaying positive dielectric anistropy and/or positive diamagnetic anisotropy.

Claim 8

A method of making an optically responsive film containing microdroplets of a birefringent nematic and/or birefringent chiral nematic liquid crystal material dispersed in a polymer film comprising mixing a liquid crystal material with the UV-curable liquid precursor mixture comprising triallyl isocyanurate and pentaerythritol tetrakis(3-mercapto-propionate) and thereafter curing the mixture in the form of a film with high intensity ultraviolet radiation to thereby form a cured polymer matrix which is a reaction product of said precursors containing dispersed therein droplets of liquid crystal material displaying positive dielectric anistropy and/or positive diamagnetic anisotropy.