Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acid esters
Reexamination Certificate
2000-03-01
2002-07-23
Raymond, Richard L. (Department: 1624)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acid esters
C204S454000, C252S299010, C522S170000, C522S181000, C526S318250, C549S464000, C549S513000, C549S539000, C549S561000, C552S010000, C552S544000, C560S122000, C560S123000, C560S124000, C560S126000, C560S220000, C560S221000
Reexamination Certificate
active
06423865
ABSTRACT:
BACKGROUND AND SUMMARY OF THE INVENTION
Polymer coatings and effect paints are extremely important for improvement of surfaces and the esthetic appearance of objects. A wide variety of color impressions and special color effects can be created in many different ways. Current polymer coatings use particles or pigments in a carrier polymer to provide color or achieve special effects such as a metallic sheen or the like. To achieve specific reflection effects, metal flakes, coated mica particles, or interference pigments based on liquid crystalline compounds for example are worked into a clear vehicle as a carrier polymer. Other pigments can additionally be added for free creation of the color impression.
Another possibility for coloration-producing effects consists in the use of liquid crystalline polymers or copolymers, oligomers (macromonomers), or monomers. Some of these liquid crystalline materials are appropriate for forming cohesive polymer films. They polymerize in the liquid crystalline phase and thus produce a paint layer with a special color effect. It is not necessary to work them into a carrier material such as a clear paint.
Known substances that exhibit a liquid crystalline state are generally elongated organic molecules which are able to assume a particular molecular arrangement. Depending on the arrangement of the liquid crystalline phase, only the wavelengths of the incident light that interfere with the equidistant lattice spacing of the liquid crystalline materials are reflected, so that particular color and reflection effects are generated. To make paints and other polymer coatings that exhibit certain wavelength reflections and light effects, it is necessary to fix the liquid crystalline phase or stabilize it mechanically. Particular liquid crystalline phases are formed in certain temperature ranges, whose position and size depends in turn on the chemical structure of the materials. Moreover, the color appearance of the liquid crystalline phases within the phase often depends on temperature, namely as the liquid crystalline phase is heated or cooled, different wavelengths are reflected. To preserve certain color or reflection effects, it is possible to fix a liquid crystalline phase by polymerization or chemical crosslinking of the initial molecules into a dense network. For this purpose, the starting materials must contain crosslinkable reactive groups.
The literature contains liquid crystalline monomer compounds with two identical terminal reactive groups such as diacrylates (J. Lub, D. J. Broer, R. A. M. Hikmet, K. G. J. Nierop, Liquid Crystals 18, 319 (1995)), diepoxides (D. J. Broer, J. Lub, G. N. Mol. Macromolecules 26, 1244 (1993)), and divinyl ethers (R. A. M. Hikmet, J. Lub, J. A. Higgins, Polymer 34, 1736 (1993); S. Jahromi, J. Lub, G. N. Mol, Polymer 35, 622 (1994)). Such monomers are usually crosslinked photochemically by photocycloaddition or by addition of a photoinitiator to the monomer mixture. Likewise, thermally initiated radical crosslinking or thermally initiated addition or condensation reactions are known. With these known monomer compounds, both terminal groups are always polymerized at the same time. To form a polymer film, the known liquid crystalline monomers are applied to the corresponding substrates and the polymerization reaction is initiated, producing the finished end product.
In this process, the application and adhesion of the initial monomers to the coated substrate create considerable difficulties. As a rule, liquid crystalline monomers are crystalline or powdered, so that they adhere poorly to the substrate and are difficult to apply in an even layer. Moreover, the known liquid crystalline materials are relatively invariable in terms of hardness, elasticity, and adhesion of the end product, namely the polymer film, and do not adjust readily to the requirements of specific applications.
The goal of the present invention is to provide compounds and a method of producing liquid crystalline polymers with better handling, processing, and end product properties than the prior art.
This goal is achieved by compounds with general formula Y
1
—A
1
—M
1
—A
2
—Y
2
wherein
Y
1
and Y
2
are different from each other and Y
1
is an acrylate or methacrylate residue and Y
2
is a vinyl ether, epoxy, or azide residue,
A
1
and A
2
are identical or different residues with the general formula C
n
H
2n
in which n is a whole number from 0 to 20 and one or more methylene groups can be replaced by oxygen atoms, and
M
1
has the general formula —R
1
—X
1
—R
2
—X
2
—R
3
—X
3
—R
4
— wherein
R
1
, R
2
, R
3
, and R
4
are identical or different covalently residues from the group —O—, —COO—, —CONH—, —CO—, —S—, —C≡C—, —CH═CH—, —CH═N—, —CH
2
—, —N═N—, and —N═N(O)—, and R
2
—X
2
—R
3
—X
3
can also be a C—C bond, and
X
1
, X
2
, and X
3
are identical or different residues from the group 1,4-phenylene, 1,4-cyclohexylene; arylalkane or heteroarylalkane with 1 to 10 carbon atoms which contains one to three heteroatoms from the group O, N, and S, substituted with B
1
, B
2
, and/or B
3
; and cycloalkylene with 1 to 10 carbon atoms and substituted with B
1
, B
2
, and/or B
3
, wherein B
1
, B
2
, and B
3
can be identical or different substituents from the group —H, C
1
-C
20
-alkyl, C
1
-C
20
-alkoxy, C
1
-C
20
-alkylthio, C
1
-C
20
-alkylcarbonyl, C
1
-C
20
-alkoxycarbonyl, C
1
-C
20
-alkylthiocarbonyl, —OH, halogen (fluorine, chlorine, bromine, iodine), —CN, —NO
2
, cycloalkyl, formyl, acetyl, and alkyl, alkoxy, or alkylthio residues with 1-20 carbon atoms interrupted by ether oxygen, thioether sulfur, or ester groups.
At the same time, a method of producing liquid crystalline polymers is provided wherein
a) prepolymers are made by polymerization, reacting the acrylate or methacrylate groups Y
1
of a compound or a mixture of compounds according to Claim 1, and thereafter
b) they are crosslinked by polymerization, reacting vinylethyl, epoxy, or azide groups Y
2
.
The particular advantage of the compounds according to the invention is that, during polymerization, particularly the creation of liquid crystalline polymers, they make a two-step process possible. The compounds proposed have a molecular structure that confers liquid crystalline properties on them. In addition, they have polymerizable residues Y
1
and Y
2
which make it possible to fix the polycrystalline phase by polymerization. By contrast to known liquid crystalline monomers, which can be used to make liquid crystalline polymer coatings, the various reactive residues Y
1
and Y
2
of the compounds according to the invention are however crosslinkable by polymerization reactions with various initiation and reaction mechanisms. By polymerization of acrylate or methacrylate groups Y
1
, prepolymers can be made with degrees of polymerization that are not too high (oligomers). These oligomers form glasses, but still do not have sufficiently low viscosity to ensure good orientation. Moreover, by the usual methods of polymer chemistry, the molecular weight and other material parameters such as viscosity, film-forming properties, leveling, flow properties, solubility, color, sheen, swelling, workability, adhesion, elasticity, hardness, etc. can be affected.
A particularly advantageous property of the reactive groups Y
1
and Y
2
of the compounds according to the invention is that the initiation and reaction of prepolymerization of reactive groups Y
1
can take place without the reactive groups Y
2
being reacted. The resultant oligomers can be readily further processed following prepolymerization and have outstanding application properties by comparison to the known polycrystal monomers. The viscosity of the prepolymers makes it possible for example to apply them before final crosslinking like a paint with good leveling properties, good flow properties, high sprayability, and outstanding adhesion to the substrate to be coated. In a further polymerization step, the vinyl ether, epoxy, or azide groups Y
2
that are still free are crosslinked. Adhesion of the end product
Barth Anne
Dannenhauer Fritz
Gailberger Michael
Grundig Petra
Stohr Andreas
Crowell & Moring LLP
Daimler-Chrysler AG
Raymond Richard L.
LandOfFree
Compounds and their application as well as a method of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Compounds and their application as well as a method of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compounds and their application as well as a method of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2817572