Polymer laminates having increased hiding power
AssigneeClariant GmbH
InventorsAxel Schoenfeld, Bernd Dewald
Life of this patent
Estimating the term…
Abstract
A polymer laminate essentially consisting of at least two cholesteric, liquid-crystalline polymer layers and a light-absorbent layer in between is suitable as starting material for effect pigments having a color impression which is dependent on the viewing angle.
Claims12
A polymer laminate consisting essentially of at least two cholesteric, liquid-crystalline polymer layers and a light-absorbent layer in between wherein the liquid-crystalline polymer of the liquid-crystalline polymer layers are main-chain polymers and the main-chain polymers consist of:
- a) from 0 to 99.9 mol % of at least one compound selected from the group consisting of aromatic hydroxycarboxylic acids, cycloaliphatic hydroxycarboxylic acids and aromatic aminocarboxylic acids;
- b) from 0 to 49.95 mol % of at least one compound selected from the group;
- consisting of aromatic dicarboxylic acids and cycloaliphatic dicarboxylic acids;
- c) from 0 to 49.95 mol % of at least one compound selected from the group consisting of aromatic diols, cycloaliphatic diols, aromatic diamines and aromatic hydroxyamines;
- d) from 0.1 to 40 mol % of chiral, bifunctional comonomers, and
- e) from 0 to 5 mol % of a branchable component containing more than two functional groups, where the sum is 100 mol %.
A process for the production of a polymer laminate wherein the polymer laminate consists essentially of at least two cholesteric, liquid-crystalline polymer layers and a light-absorbent layer in between wherein the liquid-crystalline polymer of the liquid-crystalline polymer layers are main-chain polymers and the main-chain polymers consist of:
- a) from 0 to 99.9 mol % of at least one compound selected from the group consisting of aromatic hydroxycarboxylic acids, cycloaliphatic hydroxycarboxylic acids and aromatic aminocarboxylic acids;
- b) from 0 to 49.95 mol % of at least one compound selected from the group consisting of aromatic dicarboxylic acids and cycloaliphatic dicarboxylic acids;
- c) from 0 to 49.95 mol % of at least one compound selected from the group consisting of aromatic diols, cycloaliphatic diols, aromatic diamines and aromatic hydroxyamines;
- d) from 0.1 to 40 mol % of chiral, bifunctional comonomers, and
- e) from 0 to 5 mol % of a branchable component containing more than two functional groups, where the sum is 100 mol %;
- comprising applying layers successively, optionally with interim drying or crosslinking, to a planar substrate, and detaching.
The process as claimed in 9, wherein a cholesteric, liquid-crystalline polymer, dissolved in a solvent, in which the particles forming the light-absorbent layer are dispersed is applied to a first polymer layer.
Dependencies are inferred from the claim text.