Polymeric colorants
A method of coloring a thermoplastic resin without substantially altering its clarity comprising the steps of first, providing a melt comprising a thermoplastic resin, second, adding one or more polymeric colorants to the melt, and third, mixing the thermoplastic resin and the polymeric colorants to form a colored thermoplastic resin having substantially the same clarity as the uncolored thermoplastic resin. Also provided are methods of imparting deep color to a thermoplastic resin without substantially altering its clarity comprising the steps of first, providing a melt comprising a thermoplastic resin, second, adding one or more polymeric colorants to the melt, wherein the amount of colorant is sufficient to impart a deep color, and third, mixing the thermoplastic resin and the polymeric colorants to form a deeply colored thermoplastic resin. Also provided are colored thermoplastic resins made by the methods of the present invention.
1 . A method of coloring a thermoplastic resin without substantially altering its clarity comprising the steps of:
a) providing a melt comprising a thermoplastic resin;
b) adding one or more polymeric colorants comprising a dye copolymerized into a polymeric resin to the melt; and
c) mixing the thermoplastic resin and the one or more polymeric colorants to form a colored thermoplastic resin;
wherein the polymeric colorant is a solid at room temperature; and
wherein the clarity of the thermoplastic resin is substantially the same as the clarity of the thermoplastic resin before the polymeric colorant is added.
2 . The method of claim 1 wherein the difference in clarity between the colored thermoplastic resin and the uncolored thermoplastic resin is less than 5%.
3 . The method of claim 2 wherein the difference in clarity between the colored thermoplastic resin and the uncolored thermoplastic resin is less than 1%.
4 . The method of claim 1 wherein thermoplastic resin is a clear thermoplastic resin.
5 . The method of claim 4 wherein the thermoplastic resin is clarified polypropylene.
6 . The method of claim 1 wherein the polymeric colorant is added at a level of less than 2 percent by weight.
7 . The method of claim 6 wherein the polymeric colorant is added at a level of less than 1 percent by weight.
8 . The method of claim 7 wherein the polymeric colorant is added at a level of less than 0.3% by weight.
9 . The method of claim 1 wherein the polymeric resin is selected from the group consisting of polyamides, polyamide-esters, polyesters, and combinations thereof.
10 . The method of claim 9 wherein the polymeric resin comprises a linear polymer.
11 . The method of claim 9 wherein the polymeric resin comprises a polyamide-ester.
12 . The method of claim 1 wherein the polymeric resin comprises 5 to 75% by weight dye.
13 . The method of claim 12 wherein the polymeric resin comprises 5 to 35% by weight dye.
14 . The method of claim 1 wherein the colored thermoplastic resin has a color migration value, measured as Delta E, of less than 4.
15 . The method of claim 14 wherein colored thermoplastic resin has a color migration value of less than 2.5.
16 . The method of claim 15 wherein the colored thermoplastic resin has a color migration value of less than 1.5.
17 . The method of claim 16 wherein the colored thermoplastic resin has a color migration value of less than 1.
18 . The method of claim 17 wherein the colored thermoplastic resin has a color migration value of less than 0.5.
19 . A colored thermoplastic resin as prepared by the method of claim 1 .
20 . A method for imparting a deep color to a thermoplastic resin without substantially altering the clarity of the resin, the method comprising the steps of:
a) providing a melt comprising a thermoplastic resin;
b) adding one or more polymeric colorants to the melt at a level of up to 2% by weight; and
c) mixing the thermoplastic resin and the one or more polymeric colorants to form a deeply colored thermoplastic resin;
wherein the polymeric colorant is a solid at room temperature; and
wherein the clarity of the deeply colored thermoplastic resin is substantially the same as the clarity of the thermoplastic resin before the polymeric colorant is added.
21 . The method of claim 20 wherein the thermoplastic resin is clarified polypropylene.
22 . The method of claim 20 wherein the difference in clarity between the colored thermoplastic resin and the uncolored thermoplastic resin is less than 5%.
23 . The method of claim 22 wherein the difference in clarity between the colored thermoplastic resin and the uncolored thermoplastic resin is less than 1%.
24 . The method of claim 20 wherein the polymeric colorant comprises a polymeric resin; the polymeric resin comprising a polymeric backbone and one or more dyes polymerized into the polymeric backbone; wherein the polymeric resin is selected from the group consisting of polyamides and polyester-amides; and wherein the dye is selected from the group consisting of anthraquinones, xanthenes, thioxanthenes, naphthalimides, coumarines, perylenes, methines, azo chromophores, and combinations thereof.
25 . The method of claim 24 wherein the polymeric resin comprises a linear polymer.
26 . The method of claim 20 wherein the colored thermoplastic resin has a color migration value, measured as Delta E, of less than 4.
27 . A method for imparting a deep color to a thermoplastic resin without substantially altering the clarity of the resin, comprising the steps of:
a) providing a melt comprising a thermoplastic resin;
b) adding one or more polymeric colorants to the melt; and
c) mixing the thermoplastic resin and the one or more polymeric colorants to form a colored thermoplastic resin;
wherein the polymeric colorant is a solid at room temperature;
wherein the polymeric colorant comprises a polymeric resin; the polymeric resin comprising a polymeric backbone and one or more dyes polymerized into the polymeric backbone at a level of at least 15% by weight; wherein the polymeric resin is selected from the group consisting of polyamides and polyester-amides; and
wherein the clarity of the deeply colored thermoplastic resin is substantially the same as the clarity of the thermoplastic resin before the polymeric colorant is added.
28 . The method of claim 27 wherein the thermoplastic resin is clarified polypropylene.
29 . The method of claim 27 wherein the difference in clarity between the colored thermoplastic resin and the uncolored thermoplastic resin is less than 5%.
30 . The method of claim 29 wherein the difference in clarity between the colored thermoplastic resin and the uncolored thermoplastic resin is less than 1%.
31 . The method of claim 27 wherein the polymeric resin comprises a linear polymeric backbone.
32 . The method of claim 27 wherein the dye is selected from the group consisting of anthraquinones, xanthenes, thioxanthenes, naphthalimides, coumarines, perylenes, methines, azo chromophores, and combinations thereof.
33 . The method of claim 27 wherein the colored thermoplastic resin has a color migration value, measured as Delta E, of less than 4.
34 . A method of coloring a thermoplastic resin without substantially altering the clarity of the thermoplastic resin comprising the steps of:
a) providing a melt comprising a thermoplastic resin;
b) adding one or more polymeric colorants to the melt; and
c) mixing the thermoplastic resin and the one or more polymeric colorants to form a colored thermoplastic resin;
wherein the polymeric colorant comprises a polymeric resin; the polymeric resin comprising a polymeric backbone and one or more dyes polymerized into the polymeric backbone; wherein the polymeric resin is selected from the group consisting of polyamides and polyester-amides;
wherein the polymeric colorant is solid and friable at room temperature; and
wherein the clarity of the colored thermoplastic resin is substantially the same as the clarity of the thermoplastic resin before the polymeric colorant is added.
35 . The method of claim 34 wherein the dye is selected from the group consisting of anthraquinones, xanthenes, thioxanthenes, naphthalimides, coumarines, perylenes, methines, azo chromophores, and combinations thereof.
36 . The method of claim 35 wherein the dye is a naphthalimide.
37 . The method of claim 35 wherein the dye is an anthraquinone.
38 . A polymeric colorant for coloring thermoplastic resins without substantially altering the clarity of the thermoplastic resins, the polymeric colorant comprising a polymeric resin, the polymeric resin formed from one or more monomers and one or more dyes;
wherein the monomers have at least two functional groups selected from the group consisting of amine groups, alcohol groups, carboxylic acids, and combinations thereof;
wherein at least some of the monomers are branched polyamides;
wherein the dyes are copolymerized with the monomers and are present in the polymeric colorant at a level of 5 to 75% by weight;
wherein the polymeric colorant is a solid at room temperature; and
wherein the clarity of the thermoplastic resin is not substantially altered when the polymeric colorant is added.
39 . The polymeric colorant of claim 38 wherein the dyes are selected from the group consisting of anthraquinones, xanthenes, thioxanthenes, naphthalimides, coumarines, perylenes, methines, azo chromophores, and combinations thereof.
40 . The polymeric colorant of claim 38 wherein the polymeric colorant comprises at least 15% by weight dye.
41 . The polymeric colorant of claim 40 wherein the polymeric colorant comprises 15 to 25% by weight dye.
42 . The polymeric colorant of claim 40 having a weight average molecular weight in the range from 500 to 100,000.
43 . The polymeric colorant of claim 42 having a weight average molecular weight in the range from 700 to 20,000.
44 . The polymeric colorant of claim 43 having a weight average molecular weight in the range from 1,000 to 10,000.
45 . The polymeric colorant of claim 38 having an acid number of 50 or less.
46 . The polymeric colorant of claim 38 wherein the polymeric resin comprises a linear resin.
47 . A colored thermoplastic resin comprising up to 2% by weight of a polymeric colorant of claim 38 .
48 . The colored thermoplastic resin of claim 47 wherein the colored thermoplastic resin has a color migration value, measured as Delta E, of less than 4.
49 . The colored thermoplastic resin of claim 48 wherein the colored thermoplastic resin is clarified polypropylene.