Claims
- 1. A thermosetting powder coating composition comprising a mixture of particles reactive towards one another and a catalyst, with a portion of the reactive particles comprising a polymer and an epoxy the polymer reacting with the epoxy to form ester forming and/or ether forming groups, while another portion of the reactive particles comprises an at least bifunctional cross-linking agent which contains 2-oxo-1,3-dioxolan-4-yl groups, hereinafter referred to as cyclocarbonate groups, and, optionally, functional groups that are made up almost exclusively of epoxy groups, wherein both the polymer reacting with epoxy to form ester forming and/or ether forming groups and the cross-linking agent are obtained by a non-vinylic addition and/or polymerisation process.
- 2. A powder coating composition according to claim 1, wherein the catalyst used as ring opener for the cyclocarbonate group is present in a quantity of 0.1 to 5 parts by weight per 100 parts by weight of the mixture of particles reactive towards one another.
- 3. A powder coating composition according to claim 1, wherein the quantity of epoxy oxygen present in the cross-linking agent after CO.sub.2 unblocking is at least 0.4 wt. %.
- 4. A powder coating composition according to claim 1, wherein the cyclocarbonate groups-containing cross-linking agent is obtained by reacting a corresponding polyepoxide with carbon dioxide.
- 5. A powder coating composition according to claim 1, wherein the cyclocarbonate groups-containing cross-linking agent is tris(2-oxo-1,3-dioxolanyl4-methyl)isocyanurate, which is obtained by reacting triglycidyl isocyanurate with carbon dioxide.
- 6. A powder coating composition according to claim 1, wherein the cyclocarbonate groups-containing cross-linking agent is obtained by reacting a cyclocarbonate containing a functional group with at least two groups reactive towards said functional group..
- 7. A powder coating composition according to claim 6, wherein the cyclocarbonate groups-containing cross-linking agent is obtained by reacting an HO-group-containing cyclocarbonate with a polyisocyanate.
- 8. A powder coating composition according to claim 7, wherein the polyisocyanate is the reaction product of a hydroxyfunctional compound and a low-molecular weight polyisocyanate.
- 9. A powder coating composition according to claim 1, wherein the polymer reacting with epoxy to form ester forming or ether forming groups comprises at least one functional group selected from the group consisting of carboxyl, acid anhydride and hydroxyl groups.
- 10. A powder coating composition according to claim 9, wherein the polymer reacting with epoxy to form ester forming or ether forming groups is selected from the group consisting of hydroxyl, carboxyl, and carboxylic anhydride-containing polyesters and polyurethanes.
- 11. A powder coating composition according to claim 1, wherein the glass transition temperature Tg of the polymer reacting with epoxy to form ester forming or ether forming groups is between 20.degree. and 120.degree. C.
- 12. A powder coating composition according to claim 10, wherein the polymer is a polyester having an acid number between 5 and 100 mg KOH/g, a hydroxyl number between 0 and 10 mg KOH/g, and a Tg between 30.degree. and 90.degree.C.
- 13. A powder coating composition according to claim 1, wherein the molecular weight. (Mn) of the polymer reacting with epoxy to form ester forming or ether forming groups is in the range of 800 to 10 000.
- 14. A powder coating composition according to claim 1, wherein the molecular weight (Mn) of the polymer reacting with epoxy to form ester forming or ether forming groups is in the range of 1500 to 7000.
- 15. A powder coating composition according to claim 1, wherein the molecular weight (Mn) of the cyclocarbonate groups-containing cross-linking agent is in the range of 200 to 7000.
- 16. A method comprising applying a powder coating composition in accordance with claim 1 onto a substrate by means of electrostatic spraying and curing at a temperature in the range of 140.degree. C. to 250.degree. C.
- 17. A method comprising applying a powder coating composition in accordance with claim 1 onto a substrate from an aqueous dispersion and curing at a temperature in the range of 140.degree. C. to 250.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1002008 |
Jan 1996 |
NLX |
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Parent Case Info
This is a con of PCT/EP96/05737 filed Dec. 12, 1996.
US Referenced Citations (12)
Foreign Referenced Citations (2)
Number |
Date |
Country |
4129752 |
Nov 1993 |
DEX |
4161465 |
Apr 1992 |
JPX |
Non-Patent Literature Citations (2)
Entry |
Rokicki et al., "Epoxy Resin Modified by Apliphatic Cyclic Carbonates", Journal of Applied Polymer Science, (1990), vol. 41, pp. 647-659. |
Kihara et al., "Incorporation of Carbon Dioxide into Poly(glycidyl methacrylate)", Macromolecules, (1992), vol. 25, pp. 4824-4825. |
Continuations (1)
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Number |
Date |
Country |
Parent |
PCTEP9605737 |
Dec 1996 |
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