Electrocoat composition

Patent metadata

Field	Value
Publication number	US-12398289-B2
Application number	US-202017132944-A
Country	US
Kind code	B2
Filing date	Dec 23, 2020
Priority date	Dec 30, 2019
Publication date	Aug 26, 2025
Grant date	Aug 26, 2025

Abstract

Aqueous electrocoat compositions having improved throwing power and methods for coating electrically conductive substrates are provided. An exemplary composition includes water, a crosslinkable resin including a binder and a crosslinking agent, and a pigment paste. The exemplary electrocoat composition has a pigment/binder (P/B) ratio of less than about 0.15:1.

First claim

What is claimed is:

1. An aqueous electrocoat composition comprising:
water;
a crosslinkable resin including a binder and a crosslinking agent;
a pigment paste;
a neutralizing agent for neutralizing the binder, wherein the neutralizing agent comprises at least one acid selected from the group consisting of formic acid, dimethylolpropionic acid (DMPA), lactic acid, and acetic acid, wherein the neutralizing agent has a pKa value of from 3.7 to 4.8 and is substantially free of acids having a pKa value of less than 3.7; and
a water-soluble polyvinyl alcohol (PVA) (co)polymer(s), wherein the composition comprises from 100 to about 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s),
wherein the electrocoat composition has a pigment/binder (P/B) ratio of less than 0.15:1, and
wherein the electrocoat composition, when tested according to DIN EN ISO 55655-2 with a 28 cm immersion depth, 4 mm distance, and film build outside 20-22 micrometers, exhibits a maximum throwing power range of at least 26 cm.

2. The composition of claim 1 wherein the pigment/binder (P/B) ratio is from 0.01:1 to 0.14:1, and wherein the composition comprises 100 to 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer.

3. The composition of claim 1 wherein the pigment/binder (P/B) weight ratio is from 0.1:1 to 0.13:1, and wherein the composition comprises 100 to 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer.

4. The composition of claim 3 wherein the composition comprises from 100 to 200 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s).

5. The composition of claim 1 wherein the pigment/binder (P/B) weight ratio is from 0.1:1 to 0.13:1, and wherein the composition comprises 100 to 200 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer.

6. The composition of claim 1 wherein the composition comprises about 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s).

7. The composition of claim 1 wherein the pigment paste comprises 15 to 25 wt % silica, based on the total weight of the pigment paste.

8. The composition of claim 1 wherein the composition provides a dry-film density of a coating deposited by an electrocoating process using the composition of from 1.2 to 1.3 g/cm 3 .

9. The composition of claim 1 wherein the composition provides a dry-film density of a coating deposited by an electrocoating process using the composition of from 1.2 to 1.28 g/cm 3 .

10. The composition of claim 1 wherein the composition provides a dry-film density a coating deposited by an electrocoating process using the composition of from 1.2 to 1.25 g/cm 3 .

11. An aqueous electrocoat composition comprising:
water;
a crosslinkable resin including a binder and a crosslinking agent;
a pigment paste; and
a water-soluble polyvinyl alcohol (PVA) (co)polymer(s), wherein the composition comprises from 100 to 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s),
wherein the electrocoat composition has a pigment/binder (P/B) ratio of less than 0.15:1, and
wherein the electrocoat composition, when tested according to DIN EN ISO 55655-2 with a 28 cm immersion depth, 4 mm distance, and film build outside 20-22 micrometers, exhibits a maximum throwing power range of at least 26 cm.

12. The composition of claim 11 wherein the pigment/binder (P/B) ratio is from 0.01:1 to 0.14:1.

13. The composition of claim 11 wherein the pigment/binder (P/B) weight ratio is from 0.1:1 to 0.13:1.

14. The composition of claim 11 wherein the composition comprises about 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s).

15. The composition of claim 11 wherein the composition comprises 100 to 200 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s).

16. The composition of claim 11 wherein the pigment/binder (P/B) weight ratio is from 0.1:1 to 0.13:1, and wherein the composition comprises about 300 ppm (parts per million) of the water-soluble polyvinyl alcohol (co)polymer(s).

Assignees

• Axalta Coating Systems Ip Co

Inventors

• Huesmann Thomas
• Markou Konstantinos
• Koesterke Tim

Classifications

• C25D13/06

  with polymers {(not used, see C09D5/44)} · CPC title

• C09D5/4492

  containing special additives, e.g. grinding agents · CPC title

• C09D5/4407

  with polymers obtained by polymerisation reactions involving only carbon-to-carbon unsaturated bonds · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C08K3/36

  Silica · CPC title