Use of bismuth subnitrate in electro-dipping paints

Patent metadata

Field	Value
Publication number	US-10975252-B2
Application number	US-201615277095-A
Country	US
Kind code	B2
Filing date	Sep 27, 2016
Priority date	Aug 16, 2007
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

Cathodically depositable electrocoat materials comprising basic bismuth nitrate, further comprising at least one binder having reactive functional groups and at least one crosslinker containing the complementary reactive functional groups which are able to enter into thermal crosslinking reactions.

First claim

What is claimed is:

1. A cathodically depositable electrocoat material produced by a process comprising mixing and homogenizing:
at least one binder,
at least one crosslinking agent, and
a bismuth nitrate crosslinking catalyst consisting of a water-insoluble basic bismuth nitrate,
wherein the water-insoluble basic bismuth nitrate is the only metal nitrate and the only crosslinking catalyst in the cathodically depositable electrocoat material and the cathodically depositable electrocoat material has a same or similar degree of crosslinking as an electrocoat material which contains a bismuth subsalicylate crosslinking catalyst at a baking temperature which is at least 5-10° lower than the electrocoat material which contains the bismuth subsalicylate crosslinking catalyst.

2. The electrocoat material of claim 1 , wherein the water-insoluble basic bismuth nitrate has a bismuth content of from 70% to 75% by weight.

3. The electrocoat material of claim 1 , wherein the water-insoluble basic bismuth nitrate is a bismuth subnitrate of empirical formula 4(BiNO 3 (OH) 2 ) BiO(OH).

4. The electrocoat material of claim 1 comprising relative to a solids content from 0.05% to 5% by weight of the water-insoluble basic bismuth nitrate.

5. The electrocoat material of claim 1 , wherein the binder comprises cationic groups.

6. The electrocoat material of claim 1 , wherein the binder comprises reactive functional groups that are hydroxyl groups.

7. The electrocoat material of claim 1 , wherein the crosslinking agent comprises a blocked polyisocyanate.

8. The electrocoat material of claim 1 , further comprising at least one additive from the group consisting of pigments, fillers, wetting agents, dispersants, light stabilizers, and corrosion inhibitors.

9. A process for producing the electrocoat material of claim 1 , comprising mixing the binder, and the crosslinking agent, with the bismuth nitrate crosslinking catalyst consisting of water-insoluble basic bismuth nitrate.

10. A cathodically depositable electrocoat material comprising:
about 40 to about 45 wt.-% of an aqueous binder dispersion including at least one binder that is an amino-epoxy resin and at least one crosslinking agent that is a blocked polyisocyanate;
at least one about 5 to about 6 wt. % of an aqueous pigment paste including from 0.05% to 5% by weight of a bismuth nitrate crosslinking catalyst consisting of a water-insoluble basic bismuth nitrate having a bismuth content of from 70% to 75% by weight; and
about 50 to about 52 wt. % water,
wherein the water-insoluble basic bismuth nitrate is the only metal nitrate and the only crosslinking catalyst in the cathodically depositable electrocoat material and the cathodically depositable electrocoat material has a same or similar degree of crosslinking as an electrocoat material which contains a bismuth subsalicylate crosslinking catalyst at a baking temperature which is at least 5-10° lower than the electrocoat material which contains the bismuth subsalicylate crosslinking catalyst.

11. The cathodically depositable electrocoat material of claim 10 , wherein the pigment paste further comprises titanium dioxide.

12. The cathodically depositable electrocoat material of claim 11 , wherein the pigment paste further comprises carbon black.

13. The cathodically depositable electrocoat material of claim 10 , wherein the water-insoluble basic bismuth nitrate is a bismuth subnitrate of empirical formula 4(BiNO 3 (OH) 2 ) BiO(OH).

Assignees

• Basf Coatings Gmbh

Inventors

• Grosse Brinkhaus Karl-Heinz
• Neumann Margret
• Johannpoetter Oliver
• Lux Peter

Classifications

• C09D17/005

  Carbon black · CPC title

• C08G18/0814

  containing ammonium groups or groups forming them · CPC title

• C08G18/8019

  Masked aromatic polyisocyanates · CPC title

• C09D5/4496 Primary

  characterised by the nature of the curing agents · CPC title

• C09D17/008

  Titanium dioxide · CPC title