US 2011/0255073 A1 · POLYMERIZED FILMS WITH LINE TEXTURE OR FINGERPRINT TEXTURE

Abstract

The present invention relates to a process for producing polymerized films with line texture or fingerprint texture or for producing substrates coated with polymerized films with line texture or fingerprint texture, to polymerized films, obtainable by this process, with line texture or fingerprint texture or substrates coated with polymerized films with line texture or fingerprint texture, to pigments obtainable by comminuting such films, to the use of such films, substrates or pigments as or in optical filter(s), polarizers, decorative media, forgeryproof markers, reflective media or for focusing light (in solar cells), to the use of such films as an antibacterial coating, to a forgeryproof marker which comprises such a film, and to a process for detecting forgeryproof markings.

Claims37

Dependent claims

A process for producing polymerized films with line texture or fingerprint texture or for producing substrates coated with polymerized films with line texture or fingerprint texture, comprising the following steps:

(i) providing an optionally coated carrier film or an optionally coated substrate and optionally cleaning the carrier film or the substrate and/or generating a preferential direction on the film or substrate surface or on part of the film or substrate surface;
(ii) applying a composition comprising at least one achiral nematic polymerizable monomer and optionally at least one dispersion medium to the film or substrate surface;
where the composition comprises at least one achiral nematic polymerizable monomer which is polymerizable with UV light, the composition comprising the at least one achiral nematic polymerizable monomer which is polymerizable with UV light in an amount of at least 25% by weight, based on the total weight of the achiral nematic polymerizable monomers present in the composition;
and where the composition, in the case that a film with fingerprint texture is to be obtained, also comprises at least one chiral polymerizable monomer;
(iii) optionally aligning the composition applied in step (ii) or part of the composition applied in step (ii);
(iv) at least partly removing the dispersion medium optionally present;
(v) polymerizing the at least one monomer present in the composition under the action of UV light;
(vi) optionally thermally aftertreating the product obtained in step (v);
and
(vii) optionally post-curing the product obtained in step (v) or (vi) under the action of UV light;
with the proviso that step (vi) is carried out if step (v) is carried out at a temperature of below 60° C.

8 more elements

The process according to any of the preceding claims for producing polymerized films with line texture, wherein the composition used in step (ii) does not comprise a chiral polymerizable monomer.

The process according to any of the preceding claims, wherein the at least one achiral nematic polymerizable monomer used in step (ii) comprises at least one difunctionally polymerizable achiral nematic monomer of the formula I

Z1—(Y1-A1)v-Y2-M-Y3-(A2-Y4)w—Z2 (I)
in which
Z1, Z2 are identical or different reactive groups through which polymerization can be effected, or radicals which comprise such reactive groups, where the reactive groups are selected from C═C double bonds, C═C triple bonds, oxirane, thiirane, azirane, cyanate, thiocyanate, isocyanate, carboxylic acid, hydroxyl or amino groups, and preferably from C═C double bonds;
Y1, Y2, Y3, Y4 are each independently a chemical bond, —O—, —S—, —CO—O—, —O—CO—, —O—CO—O—, —CO—S—, —S—CO—, —CO—N(Ra)—, —N(Ra)—CO—, —N(Ra)—CO—O—, —O—CO—N(Ra)—, —N(Ra)—CO—N(Ra)—, —CH2—O—, —O—CH2—, preferably —CO—O—, —O—CO— or —O—CO—O—, where Ra is hydrogen or C1-C4-alkyl;
A1, A2 are identical or different spacers selected from linear C2-C30-alkylene groups, preferably C2-C12-alkylene groups, which may be interrupted by oxygen, sulfur and/or optionally monosubstituted nitrogen, where these interrupting groups must not be adjacent;
where suitable amine substituents comprise C1-C4-alkyl groups, where the alkylene chains may be substituted by fluorine, chlorine, bromine, cyano, methyl or ethyl;
and where, more preferably, A1 and A2 are each —(CH2)n— where n=2 to 8;
v and w are each independently 0, 1 or 2;
M is a mesogenic group of the general formula II:
(T1-Y5)y-T2 (II)
in which
each T1 is independently a divalent alicyclic, saturated or partially unsaturated heterocyclic, aromatic or heteroaromatic radical;
T2 is defined independently as T1 or is a —CH═N—N═CH— group;
Y5 is identical or different bridging members —CO—O—, —O—CO—, —CH2—O—, —O—CH2—, —CO—S—, —S—CO—, —CH2—S—, —S—CH2, —CH═N—, —N═CH—, —CH═N—N═CH—, —CH═CH—, —C(CH3)═CH2, —CH═CH(CH3)— or a direct bond, and
y is 0, 1, 2 or 3, preferably 0, 1 or 2, particularly 1 or 2 and especially 2.

12 more elements

The process according to any of the preceding claims, wherein the composition used in step (ii) comprises at least one photoinitiator.

The process according to any of the preceding claims, wherein the layer thickness of the polymer film which is formed from the composition applied in step (ii) after performance of step (v) is 0.1 to 10 μm, preferably 0.5 to 5 μm, especially 0.9 to 3.5 μm.

Dependencies are inferred from the claim text.

Polymerized films with line texture or fingerprint texture

Life of this patent

Polymerized films with line texture or fingerprint texture

Life of this patent

Abstract

Claims37