Effect coating material and effect coating system, especially for vehicle bodies, using liquid-crystalline interference pigments

A process for the preparation of platelet-like interference pigments comprising:

• producing a film of molecules having at least one of an nematic, smectic and cholesteric order by applying liquid-crystalline side-chain polymers in a liquid state to a smooth substrate,
• curing the film,
• removing the cured film from the substrate,
• comminuting the cured film into platelet-like particles, and
• separating out particles having a diameter smaller than the film thickness and particles having a diameter which is more than ten times the film thickness by a particle size-selective separation process before subsequently processing the remaining particles as interference pigments,
• wherein
• the film of liquid-crystalline side-chain polymers is applied as a solvent application or melted powder, wherein
• the liquid-crystalline side-chain polymers are formed by crosslinking starting components,
• the starting components comprise a nematic component and a chiral component,
• the nematic component is selected from the group of mono- and difunctional low molar mass compounds consisting of:
• 1. 4-diphenyl di›4-(acryloyloxy)alkyloxy!benzoates,
• 1,4-di(2-methyl)phenyl di›4-(acryloyloxy)alkyloxy!-benzoates,
• 1,4-di(2-methoxy)phenyl di›4-(acryloyloxy)alkyloxy!-benzoates, and
• mixtures thereof, and
• the chiral component is selected from the group of optically isomeric low molar mass compounds having a chiral center consisting of:
• 3,5-cholesteryl (acryloyloxyalkoxy)benzoate,
• 3. 4-cholesteryl (acryloyloxyalkoxy)benzoate,
• 2,5-cholesteryl (acryloyloxyalkoxy)benzoate,
• 2,4-cholesteryl (acryloyloxyalkoxy)benzoate,
• .beta.-oestra-3,17-diyl (acryloyloxyalkoxy)benzoate,
• .beta.-oestra-3,17-diyl acrylate,
• R- or S-1,1'-bi-2-naphthoyl›4-alkoxybenzoyloxy-(4,4-biphenyloyloxyalkoxyacrylate ),
• R- or S-1,1'-bi-2-naphthoyl›hexylterephthaloyl!-(4,4-biphenyloyloxyalkoxyacrylat e),
• 1,4-diphenyl R- or S-di›4-(3-acryloyloxy-2-methyl-propoxy)benzoate!,
• 2-octyl 4-(4-hexyloxybenzoyloxy!benzoate,
• 1,4-diphenyl di›4-(3-acryloyloxy-2-methylpropoxy!-benzoate,
• 1,4-di(2-methyl)phenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(3-acryloyloxy-2-metholpropoxy!benzoate,
• 1,4-diphenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(1-acryloyloxy-1-methyl-ethoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4(1-acryloyloxy-1-methylethoxy!benzoate,
• 1. 4-diphenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate, and
• mixtures thereof.

A coating material for painting articles comprising interference pigments which are incorporated by mixing, wherein at least some of the interference pigments are platelet-like and automatically align themselves approximately parallel to the surface of the article during application of the coating material, and are composed of liquid-crystalline side-chain polymers, comprising side-chain mesogens have at least one of an nematic, smectic and cholesteric order, wherein:

• the liquid-crystalline side-chain polymers are formed by crosslinking starting components,
• the starting components comprise a nematic component and a chiral component,
• the nematic component is selected from the group of mono- and difunctional low molar mass compounds consisting of:
• 1,4-diphenyl di›4-(acryloyloxy)alkyloxy!benzoates,
• 1,4-di(2-methyl)phenyl di›4-(acryloyloxy)alkyloxy!benzoates,
• 1,4-di(2-methoxy)phenyl di›4-(acryloyloxy)alkyloxy!benzoates, and
• mixtures thereof, and
• the chiral component is selected from the group of optically isomeric low molar mass compounds having a chiral center consisting of:
• 3,5-cholesteryl (acryloyloxyalkoxy)benzoate,
• 3,4-cholesteryl (acryloyloxyalkoxy)benzoate,
• 2,5-cholesteryl (acryloyloxyalkoxy)benzoate,
• 2,4-cholesteryl (acryloyloxyalkoxy)benzoate,
• .beta.-oestra-3,17-diyl (acryloyloxyalkoxy)benzoate,
• .beta.-oestra-3,17-diyl acrylate,
• R- or S-1,1'-bi-2-naphthoyl›4-alkoxybenzoyloxy!(4,4-biphenyloyloxyalkoxyacrylate ),
• R- or S-1,1'-bi-2-naphthoyl›hexylterephthaloyl!(4,4-biphenyloyloxyalkoxyacrylate ),
• 1. 4-diphenyl R- or S-di›4-(3-acryloyloxy-2-methylpropoxy)benzoate!,
• 2-octyl 4-(4-hexyloxybenzoyloxy!benzoate,
• 1,4-diphenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-diphenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1,4-diphenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate, and
• mixtures thereof.

A coating system for application to an article to define the color of the article, comprising a color-defining coating layer comprising pigments, wherein at least some of the pigments are interference pigments, wherein depending on the desired color of the article, the interference pigments are platelet-like and align themselves approximately parallel to the surface of the article and consist of crosslinked liquid-crystalline side-chain polymers, comprising side-group mesogens having at least one of an nematic, smectic and cholesteric order, wherein:

• the liquid-crystalline side-chain polymers are formed by crosslinking starting components,
• the starting components comprise a nematic component and a chiral component,
• the nematic component is selected from the group of mono- and difunctional low molar mass compounds consisting of:
• 1,4-diphenyl di›4-(acryloyloxy)alkyloxy!benzoates,
• 1,4-di(2-methyl)phenyl di›4-(acryloyloxy)alkyloxy!benzoates,
• 1,4-di(2-methoxy)phenyldi›4-(acryloyloxy) alkyloxy!benzoates, and
• mixtures thereof, and
• the chiral component is selected from the group of optically isomeric low molar mass compounds having a chiral center consisting of:
• 3,5-cholesteryl (acryloyloxyalkoxy) benzoate,
• 3,4-cholesteryl (acryloyloxyalkoxy) benzoate,
• 2,5-cholesteryl (acryloyloxyalkoxy)benzoate,
• 2,4-cholesteryl (acryloyloxyalkoxy) benzoate,
• .beta.-oestra-3,17-diyl (acryloyloxyalkoxy)benzoate,
• .beta.-oestra-3,17-diyl acrylate,
• R- or S-1,1'-bi-2-naphthoyl›4-alkoxybenzoyloxy!(4,4-biphenyloyloxyalkoxyacrylate ),
• R- or S-1,1'-bi-2-naphthoyl›hexylterephthaloyl!(4,4-biphenyloyloxyalkoxyacrylate ),
• 1,4-diphenyl R- or S-di›4-(3-acryloyloxy-2-methylpropoxy)benzoate!,
• 2-octyl 4-(4-hexyloxybenzoyloxy!benzoate,
• 1,4-diphenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(3-acryloyloxy-2-methylpropoxy!benzoate,
• 1,4-diphenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1,4-di(2-methyl)phenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(1-acryloyloxy-1-methylethoxy!benzoate,
• 1. 4-diphenyl di›4-(6-acryloyloxy-3-methylhexoxy!-benzoate,
• 1,4-di(2-methyl)phenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate,
• 1,4-di(2-methoxy)phenyl di›4-(6-acryloyloxy-3-methylhexoxy!benzoate, and
• mixtures thereof.