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EP-4424787-B1 - METHOD FOR PREPARING PYRROLE POLYMERS

EP4424787B1EP 4424787 B1EP4424787 B1EP 4424787B1EP-4424787-B1

Inventors

  • BODINO, Frederic Jean Alain
  • HUDSON, Melissa Dawn Lee
  • MARTENS, Paul Xavier
  • NEAGU, Claudiu
  • KARMAN, Marc

Dates

Publication Date
20260513
Application Date
20210331

Claims (19)

  1. An ink composition, comprising: a copolymer comprising i) a polypyrrole and ii) at least one of a polyol, a polyether, a polyketone, a vinyl polymer, or a polyolefin, and an organic solvent, wherein the composition is a solution and the copolymer is in an amount of from about 1% to about 70% by weight of the composition.
  2. The composition of claim 1, wherein the polypyrrole comprises a pyrrole substituted by at least one C 1 -C 20 alkyl or C 1 -C 20 alkylene group as a monomer repeat unit, the C 1 -C 20 alkyl or C 1 -C 20 alkylene group being optionally substituted by OH, aryl, or C(O)R, in which R is C 1 -C 4 alkyl.
  3. The composition of claim 2, wherein the C 1 -C 20 alkyl group is isobutyl.
  4. The composition of claim 2, where the at least one C 1 -C 20 alkyl group is at the 3-position, or 4-position, or both the 3- and 4-positions on the pyrrole ring.
  5. The composition of claim 1, wherein the polypyrrole comprises a monomer repeat unit of formula (I) or (II): in which each of R 1 , R 2 , R 3 , and R 4 , independently, is H or C 1 -C 20 alkyl optionally substituted by OH, aryl, or C(O)R; R 3 is linear or branched C 1 -C 20 alkylene optionally substituted by OH, aryl, or C(O)R; and each R, independently, is C 1 -C 4 alkyl, optionally wherein each of R 1 , R 2 , R 3 , and R 4 , independently, is H or isobutyl, or R 3 is isobutylene.
  6. The composition of claim 1, wherein the polypyrrole comprises first and second pyrrole monomer repeat units, and the first pyrrole monomer repeat unit is different from the second pyrrole monomer repeat unit.
  7. The composition of claim 1, wherein the polypyrrole is in an amount of from about 10 wt% to about 60 wt% of the composition.
  8. The composition of claim 1, wherein the organic solvent comprises a ketone, an ester, an acetal, an ether, a carbonate, an ester, or a combination thereof, or wherein the organic solvent comprises methyl ethyl ketone, methyl isobutyl ketone, methyl isopropyl ketone, diethyl ketone, cyclopentanone, acetone, methyl acetate, ethyl acetate, methanol, ethanol, isopropanol, chloroform, dimethylsulfoxide, propylene carbonate, ethylene glycol, propylene glycol, propylene glycol monomethyl ether, or tripropylene glycol monomethyl ether.
  9. The composition of claim 1, wherein the organic solvent is in an amount of from about 30 wt% to about 99 wt% of the composition.
  10. The composition of claim 1, further comprising a rheology agent, optionally wherein the rheology agent comprises nitrocellulose, cellulose acetate butyrate, cellulose acetate, shellac, a rosin ester, a polyurethane, an acrylic, or a conductive polymer, , and optionally wherein the rheology agent is in an amount of from about 1 wt% to about 30 wt% of the composition.
  11. The composition of claim 1, further comprising a dopant, optionally wherein the dopant comprises an inorganic acid, a carboxylic acid, a sulfonic acid, an organophosphoric acid, or a salt thereof, optionally wherein the dopant is hydrochloric acid, sulfuric acid, phosphoric acid, perchloric acid, fluoroboric acid, 4-dodecyl benzene sulfonic acid, triflic acid, trifluoroacetic acid, p-toluenesulfonic acid, hydroxyanthroquinone sulfonic acid, camphor sulfonic acid, a quinone sulfonic acid, phthalocyanine tetrasulfonic acid, a poly(styrene sulfonic acid) or a copolymer thereof, or a salt thereof, and optionally wherein the dopant is in an amount of from about 1 wt% to about 55 wt% of the composition.
  12. The composition of claim 1, further comprising a colorant, a surfactant, a conductive agent, a humectant, or a resin, optionally wherein the colorant comprises a dye or a pigment.
  13. The composition of claim 1, wherein the copolymer has a solubility of at least about 1% by weight in an organic solvent at 25°C.
  14. The composition of claim 1, wherein the composition has a conductivity of from about 0 µS/cm to about 8000 µS/cm.
  15. The composition of claim 1, wherein the composition has an apparent viscosity of from about 1 mPa.s (cP) to about 25 mPa.s (cP) measured at 20°C and 60 rpm.
  16. The composition of claim 1, wherein the composition has a surface tension of from about 20 mN/m (dynes/cm) to about 30 mN/m (dynes/ cm) at 25°C.
  17. A product, comprising a substrate and a solid ink defining an image on the substrate, the solid ink comprising the ink composition of any one of claims 1 to 16.
  18. The product of claim 17, wherein the substrate is a cardboard, a glass, a metal, or a film.
  19. A printing process, comprising: ejecting the ink composition of any one of claims 1 to 16 from a printhead in an inkjet printer onto a substrate to form an image.

Description

CROSS REFERENCE TO RELATED APPLICATION This application claims priority under 35 USC §119(e) to U.S. Provisional Application Serial No. 63/002,722, filed on March 31, 2020. TECHNICAL FIELD This disclosure relates to polypyrrole polymers, as well as related ink compositions, products, and processes. BACKGROUND During ink jet printing, the ink is typically ejected through a component of a printhead (e.g., an array of nozzles) onto a substrate. Many solvent-soluble dyes currently used in the ink jet printing have been identified as toxic materials. These dyes are typically coordinated to heavy metals, which could contribute to the toxicity of such dyes. Thus, there is a need to develop a solvent-soluble dye that does not contain heavy metals. Relevant prior art documents represent EP2452982 A1 and WO03/018648 A1. SUMMARY This disclosure is based on the unexpected discovery that certain polypyrrole polymers can have a relatively high solubility in an organic solvent and can form a colorant without including any heavy metal. Such a polypyrrole can be used as a black dye in a continuous inkjet (CIJ) printing process or a drop-on-demand (DOD) printing process (e.g., a thermal inkjet (TIJ) printing process). Compared to conventional colorants (e.g., carbon black and metal complexed dyes) used in a printing processes (e.g., CIJ or DOD), the polypyrrole described herein can form a simplified ink composition (e.g., without including a dispersant, a binder, and/or a rheology agent) while still possessing excellent stability, printablility, and adhesion to a variety of substrates. In one aspect, this disclosure features an ink composition that includes a copolymer comprising i) a polypyrrole and ii) at least one of a polyol, a polyether, a polyketone, a vinyl polymer, or a polyolefin, and an organic solvent, wherein the composition is a solution and the copolymer is in an amount of from 1% to 70% by weight of the composition. In another aspect, this disclosure features a product that includes a substrate (e.g., a cardboard, a glass, a metal, or a film) and a solid ink defining an image on the substrate, in which the solid ink includes the ink composition described herein. In another aspect, this disclosure features a printing process that includes ejecting the ink composition described herein from a printhead in an inkjet printer onto a substrate to form an image. In another aspect, this disclosure features a polymer that includes a polypyrrole, in which the polypyrrole contains a monomer repeat unit that includes a pyrrole substituted by at least one C1-C20 alkyl group as a monomer repeat unit, the C1-C20 alkyl group being optionally substituted by OH, aryl, or C(O)R, in which R is C1-C4 alkyl. In another aspect, this disclosure features a polymer that includes a polypyrrole copolymer, in which the polypyrrole copolymer includes a first polymer unit and a second polymer unit, the first polymer unit includes an unsubstituted polypyrrole, and the second polymer unit includes a substituted polypyrrole, a polyol, a polyether, a polyketone, a vinyl polymer, or a polyolefin. In another aspect, this disclosure features a method of preparing a polypyrrole polymer that includes (1) mixing pyrrole with a solution containing at least one ketone or aldehyde compound to form an intermediate product; and (2) mixing the intermediate product with at least one oxidizing reagent to form a polypyrrole polymer. In still another aspect, this disclosure features a method of preparing a polypyrrole copolymer that includes (1) mixing at least one ketone or aldehyde compound with at least one first oxidizing reagent to form an intermediate product; and (2) mixing the intermediate product with pyrrole to form a polypyrrole copolymer. Embodiments can have one or more of the following features. In some embodiments, the polypyrrole includes a pyrrole substituted by at least one C1-C20 alkyl (e.g., isobutyl) or C1-C20 alkylene (e.g., isobutylene) group as a monomer repeat unit, the C1-C20 alkyl or C1-C20 alkylene group being optionally substituted by OH, aryl, or C(O)R, in which R is C1-C4 alkyl. In some embodiments, the at least one C1-C20 alkyl group is at the 3-position, or 4-position, or both the 3- and 4-positions on the pyrrole ring. In some embodiments, the at least one C1-C20 alkylene group is at the 2-position, or 5-position, or both the 2- and 5-positions on the pyrrole ring. In some embodiments, the polypyrrole includes a monomer repeat unit of formula (I) or (II): in which each of R1, R2, R3, and R4, independently, is H or C1-C20 alkyl optionally substituted by OH, aryl (e.g., phenyl), or C(O)R; R3 is linear or branched C1-C20 alkylene optionally substituted by OH, aryl, or C(O)R; and each R, independently, is C1-C4 alkyl. In some embodiments, each of R1, R2, R3, and R4, independently, is H or isobutyl. In some embodiments, R3 isobutylene. In some embodiments, the polypyrrole includes first and second pyrrole monomer repeat units, and