Matt powder coatings

1. A branched carboxylic acid functional polyester resin P1, having:

(a) a Tg of at least 40° C. as measured by Differential Scanning Calorimetry (DSC) at a heating rate of 5° C./min;

(b) an acid value (AV) of at least 20 and of at most 30 mg KOH/g of the polyester resin P1;

(c) a hydroxyl value of at most 7 mg KOH/g of the polyester resin P1; and

(d) a functionality of at least 2.1 and of at most 3; wherein

the polyester resin P1 is a reaction product of at least the following monomers:

i) neopentyl glycol in an amount of at least 25 and at most 50 mol %;

ii) ethylene glycol in an amount of at least 5 and at most 20 mol %;

iii) a C 6 diol in an amount of at least 1.5 and at most 4.7 mol %;

iv) isophthalic acid in an amount of at least 0 and at most 6.5 mol %;

v) terephthalic acid in an amount of at least 39 and at most 48 mol %;

vi) adipic acid in an amount of at least 1 and at most 10 mol %; and

vii) an at least trifunctional monomer in an amount of at least 0.001 and at most 3 mol %; and wherein

the mol % is based on a total amount of monomers i)-vii) forming the polyester resin P1 being 100 mol %.

2. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the AV is at most 29 mg KOH/g of the polyester resin P1.

3. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the AV is at least 20 and at most 28 mg KOH/g of the polyester resin P1.

4. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the amount of the at least trifunctional monomer is at least 0.01 and at most 2.5 mol %.

5. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the hydroxyl value is at most 6 mg KOH/g of the polyester resin P1.

6. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the hydroxyl value is at most 5 mg KOH/g of the polyester resin P1.

7. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the hydroxyl value is at most 4.5 mg KOH/g of the polyester resin P1.

8. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the hydroxyl value is at most 4.2 mg KOH/g of the polyester resin P1.

9. The branched carboxylic acid functional polyester resin P1 according to claim 1 , wherein the hydroxyl value is at most 4 mg KOH/g of the polyester resin P1.

10. A thermosetting powder coating composition A1 (PCC A1) comprising a binder K1 in an amount of at least 20 and at most 100 pph PCC A1, said binder K1 comprising:

a crosslinker X1 in an amount of at least 1 and at most 55 pph of the binder K1, wherein the crosslinker X1 is selected from the group consisting of epoxy compounds, BHA compounds having at leest two β-hydroxyalkylamide groups and mixtures thereof; and

the branched carboxylic acid functional polyester resin P1 according to claim 1 in an amount of at least 45 and at most 99 pph of the binder K1.

11. The thermosetting powder coating composition A1 (PCC A1) according to claim 10 , wherein the crosslinker X1 is a BHA compound.

12. A cured thermosetting powder coating composition which obtained by curing the thermosetting powder coating composition A1 as defined in claim 11 .

13. A The coated article having a cured coating thereon, wherein the cured coating is obtained by curing the thermosetting powder coating composition according to claim 12 .

14. A coated article having a coating thereon comprised of the thermosetting powder coating composition A1 according to claim 11 .

15. A two component (2k) thermosetting powder coating composition B (PCC B), comprising a physical mixture of two different, separate and distinct thermosetting powder coating compositions A (PCC A) and A1 (PCC A1), wherein PCC A1 is according to claim 10 , and wherein PCC A and PCC A1 are present in PCC B in a total amount which is at least 30 pph of PCC B, and wherein the weight ratio R=weight PCC A/weight PCC A1 is at least 0.3 (and at most 3, and wherein

PCC A comprises a binder K in an amount of at least 20 and at most 100 pph PCC A, wherein the binder K comprises:

a crosslinker X in an amount of at least 1 and at most 55 pph of binder K, wherein the crosslinker X is selected from the group consisting of epoxy compounds, BHA compounds having at least two β-hydroxyalkylamide groups and mixtures thereof; and

a branched carboxylic acid functional polyester resin P in an amount of at least 45 and at most 99 pph of binder K, wherein

the polyester resin P has:

(a) a Tg of at least 40° C. as measured by Differential Scanning calorimetry (DSC) at a heating rate of 5° C./min;

(b) an acid value (AV) of at least 65 and of at most 76.8 mg KOH/g of the polyester resin P;

(c) a hydroxyl value of at most 10 mg KOH/g of the polyester resin P; and

(d) a functionality of at least 3.5 and at most 5; and wherein

the polyester resin P is a reaction product of at least the following monomers:

i) neopentyl glycol in an amount of at least 19 and at most 38 mol %;

ii) ethylene glycol in an amount of at least 8 and at most 21 mol %;

iii) a polyol in an amount of at least 0 and at most 2 mol %;

iv) isophthalic acid in an amount of at least 0 and at most 2.4 mol %;

v) terephthalic acid in an amount of at least 38 and at most 47 mol %;

vi) adipic acid in an amount of at least 0.01 and at most 10 mol %; and

vii) a polycarboxylic acid, in an amount of at least 6 and at most 10.2 mol %; and wherein

the mol % is based on a total amount of monomers i)-vii) forming the polyester resin P being 100 mol %.

16. The thermosetting powder coating composition B according to claim 15 , wherein the amount of the polyol monomer iii) is at least 0 and at most 1.4 mol %.

17. The thermosetting powder coating composition B according to claim 15 , wherein the AV is at least 68 mg KOH/g of the polyester resin P.

18. The thermosetting powder coating composition B according to claim 15 , wherein the neopentyl glycol monomer i) is present in an amount of at most 36.5 mol %.

19. The thermosetting powder coating composition B according to claim 15 , wherein the polycarboxylic acid is present in an amount of at least 6.5 mol %.

20. The thermosetting powder coating composition B according to claim 15 , wherein the weight ratio R is at least 0.4 and at most 2.5.

21. The thermosetting powder coating composition B according to claim 15 , wherein the weight ratio R is at least 0.6 and at most 1.5.

22. The thermosetting powder composition B according to claim 15 , wherein the crosslinker X is a BHA compound and the crosslinker X1 is a BHA compound.

23. A cured thermosetting powder coating composition which obtained by curing the thermosetting powder coating composition A1 as defined in claim 15 .

24. A coated article having a cured coating thereon, wherein the cured coating is obtained by curing the thermosetting powder coating composition according to claim 23 .

25. A coated article having a coating thereon comprised of the thermosetting powder coating composition B according to claim 15 .

26. A process for making an article having a coating of a cured thermosetting powder coating composition B, wherein the process comprises the steps of:

(a) applying the thermosetting powder coating composition B according to claim 15 to an article to form a coating thereon; and

(b) heating and/or radiating the coating of the thermosetting powder coating composition B for enough time and at a suitable temperature to cure the thermosetting powder coating composition B to thereby obtain the article having a coating of the cured thermosetting powder coating composition B.

27. A cured thermosetting powder coating composition which obtained by curing the thermosetting powder coating composition A1 as defined in claim 10 .

28. A coated article having a cured coating thereon, wherein the cured coating is obtained by curing the thermosetting powder coating composition according to claim 27 .

29. A coated article having a coating thereon comprised of the thermosetting powder coating composition A1 according to claim 10 .

30. A process for making an article having coated and cured thereon a thermosetting powder coating composition A1, wherein the process comprises the steps of:

(a) applying the thermosetting powder coating composition A1 according to claim 10 to an article to form a coating thereon; and

(b) heating and/or radiating the coating of the thermosetting powder coating composition A1 for enough time and at a suitable temperature to cure the thermosetting powder coating composition A1 to thereby obtain the article having a coating of the cured thermosetting powder coating composition A1.