Thermosetting powder coating compositions comprising dilauroyl peroxide

Abstract

The invention relates to thermosetting powder coating compositions as these are disclosed herein. The compositions comprise certain unsaturated resins comprising ethylenic unsaturations, curing agents selected from vinyl urethanes, vinyl functionalized urethane resins and mixtures thereof, dilauroyl peroxide as initiator, and a co-initiator selected from the group of onium compounds and sulpho-compounds. The invention further relates to a process for making said thermosetting powder coating compositions and processes for coating an article with said thermosetting powder coating compositions. The invention further relates to cured thermosetting powder coating compositions obtained by curing of the thermosetting powder coating compositions of the invention. The invention further relates to an article having coated thereon said thermosetting powder coating composition as well as to an article having coated and cured thereon said thermosetting powder coating composition. The invention further relates to the use of said thermosetting powder coating compositions, to the use of an article having coated thereon said thermosetting powder coating compositions and to the use of an article having coated and cured thereon said thermosetting powder coating compositions. The invention further relates to various uses of either the thermosetting powder coating compositions of the invention, or the cured thermosetting powder coating compositions of the invention or of articles having coated thereon the thermosetting powder coating composition of the invention, or of articles having coated and cured thereon the thermosetting powder coating composition of the invention. The invention further relates to a method for enabling the fast heat-curing of a thermosetting powder coating composition at low temperature. The invention further relates to a method for enhancing the chemical resistance of a powder coating obtained by heat curing of the thermosetting powder coating composition of the invention at low temperature.

Claims

1. A thermosetting powder coating composition comprising the following components A to D: A: one or more unsaturated resins comprising ethylenic unsaturations (UR) selected from the group consisting of polyester resins, acrylic resins, polyurethanes, epoxy resins, polyamides, polyesteramides, polycarbonates, polyureas and mixtures thereof, and B: one or more curing agents selected from the group consisting of vinyl urethanes, vinyl functionalized urethane resins and mixtures thereof, wherein at least one curing agent is curing agent A which is selected from the group consisting of i), ii) and iii): i) one or more crystalline VU-c each of which is a crystalline vinyl urethane having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the one or more crystalline VU-c are in the region of from and including 30 up to and including 80° C., and ii) one or more crystalline VFUR-c each of which is a crystalline vinyl functionalized urethane resin having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the one or more crystalline VFUR-c are in the region of from and including 30 up to and including 80° C., and iii) mixtures of crystalline VU-c and crystalline VFUR-c, wherein the ΔH.sub.m and T.sub.m is each measured via Differential Scanning calorimetry (DSC), C: one or more thermal radical initiators, wherein at least one thermal radical initiator is dilauroyl peroxide and wherein the dilauroyl peroxide is present in an amount of at least 30 and at most 190 mmol/Kg A and B, and D: one or more co-initiators selected is selected from the group consisting of onium compounds, sulpho-compounds, and mixtures thereof, and wherein the total amount of component D is at least 10 and at most 300 mmol/Kg A and B.

2. The thermosetting powder coating composition according to claim 1, wherein the dilauroyl peroxide is present in an amount of at least 35 mmol/Kg A and B.

3. The thermosetting powder coating composition according to claim 1, wherein the dilauroyl peroxide is present in an amount of at least 40 mmol/Kg A and B.

4. The thermosetting powder coating composition according to claim 3, wherein the total amount of the component C is at most 250 mmol/Kg A and B.

5. The thermosetting powder coating composition according to claim 4, wherein the total amount of the component C is at most 190 mmol/Kg A and B.

6. The thermosetting powder coating composition according to claim 5, wherein the onium compounds of component D are selected from the group consisting of compounds represented by the following formula I-X and compounds represented by the following formula II-X: ##STR00045## wherein A.sup.− is selected from the group consisting of halide anions; and R.sub.1′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl, and R.sub.2′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl.

7. The thermosetting powder coating composition according to claim 6, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

8. The thermosetting powder coating composition according to claim 7, wherein the curing agent A is present in an amount of at least 70 pph of B.

9. The thermosetting powder coating composition according to claim 6, wherein the curing agent A is present in an amount of at least 70 pph of B.

10. The thermosetting powder coating composition according to claim 6, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

11. The thermosetting powder coating composition according to claim 5, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

12. The thermosetting powder coating composition according to claim 11, wherein the curing agent A is present in an amount of at least 70 pph of B.

13. The thermosetting powder coating composition according to claim 5, wherein the curing agent A is present in an amount of at least 70 pph of B.

14. The thermosetting powder coating composition according to claim 5, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

15. The thermosetting powder coating composition according to claim 4, wherein the onium compounds of component D are selected from the group consisting of compounds represented by the following formula I-X and compounds represented by the following formula II-X: ##STR00046## wherein A.sup.− is selected from the group consisting of halide anions; and R.sub.1′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl, and R.sub.2′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl.

16. The thermosetting powder coating composition according to claim 15, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

17. The thermosetting powder coating composition according to claim 16, wherein the curing agent A is present in an amount of at least 70 pph of B.

18. The thermosetting powder coating composition according to claim 15, wherein the curing agent A is present in an amount of at least 70 pph of B.

19. The thermosetting powder coating composition according to claim 15, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

20. The thermosetting powder coating composition according to claim 4, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

21. The thermosetting powder coating composition according to claim 20, wherein the curing agent A is present in an amount of at least 70 pph of B.

22. The thermosetting powder coating composition according to claim 4, wherein the curing agent A is present in an amount of at least 70 pph of B.

23. The thermosetting powder coating composition according to claim 4, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

24. The thermosetting powder coating composition according to claim 3, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

25. The thermosetting powder coating composition according to claim 24, wherein the curing agent A is present in an amount of at least 70 pph of B.

26. The thermosetting powder coating composition according to claim 3, wherein the curing agent A is present in an amount of at least 70 pph of B.

27. The thermosetting powder coating composition according to claim 3, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

28. The thermosetting powder coating composition according to claim 1, wherein the dilauroyl peroxide is present in an amount of at least 45 mmol/Kg A and B.

29. The thermosetting powder coating composition according to claim 28, wherein the total amount of the component C is at most 250 mmol/Kg A and B.

30. The thermosetting powder coating composition according to claim 29, wherein the total amount of the component C is at most 190 mmol/Kg A and B.

31. The thermosetting powder coating composition according to claim 28, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

32. The thermosetting powder coating composition according to claim 31, wherein the curing agent A is present in an amount of at least 70 pph of B.

33. The thermosetting powder coating composition according to claim 28, wherein the curing agent A is present in an amount of at least 70 pph of B.

34. The thermosetting powder coating composition according to claim 28, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

35. The thermosetting powder coating composition according to claim 1, wherein the total amount of the component C is at most 250 mmol/Kg A and B.

36. The thermosetting powder coating composition according to claim 35, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

37. The thermosetting powder coating composition according to claim 36, wherein the curing agent A is present in an amount of at least 70 pph of B.

38. The thermosetting powder coating composition according to claim 35, wherein the curing agent A is present in an amount of at least 70 pph of B.

39. The thermosetting powder coating composition according to claim 35, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

40. The thermosetting powder coating composition according to claim 1, wherein the total amount of the component C is at most 190 mmol/Kg A and B.

41. The thermosetting powder coating composition according to claim 1, wherein the onium compounds of component D are selected from the group consisting of compounds represented by the following formula I-X and compounds represented by the following formula II-X: ##STR00047## wherein A.sup.− is selected from the group consisting of halide anions; and R.sub.1′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl, and R.sub.2′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl.

42. The thermosetting powder coating composition according to claim 41, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

43. The thermosetting powder coating composition according to claim 42, wherein the curing agent A is present in an amount of at least 70 pph of B.

44. The thermosetting powder coating composition according to claim 41, wherein the curing agent A is present in an amount of at least 70 pph of B.

45. The thermosetting powder coating composition according to claim 41, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

46. The thermosetting powder coating composition according to claim 1, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

47. The thermosetting powder coating composition according to claim 46, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

48. The thermosetting powder coating composition according to claim 1, wherein the curing agent A is present in an amount of at least 70 pph of B.

49. The thermosetting powder coating composition according to claim 48, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A, which is at least 0.60 and at most 3.

50. The thermosetting powder coating composition according to claim 1, wherein the curing agent A is present in an amount of at least 80 pph of B.

51. The thermosetting powder coating composition according to claim 1, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A which is at least 0.60 and at most 3.

52. The thermosetting powder coating composition according to claim 1, wherein K is a ratio of the total mol of the ethylenic unsaturations in B divided by the total mol of the ethylenic unsaturations in A which is at least 0.95 and at most 2.5.

53. The thermosetting powder coating composition according to claim 1, wherein the curing agent A has a crystallization temperature (T.sub.c) measured by Differential Scanning calorimetry (DSC) of at least 10 and at most 70° C.

54. The thermosetting powder coating composition according to claim 1, wherein the total amount of the component D is at most 150 mmol/Kg A and B.

55. The thermosetting powder coating composition according to claim 1, wherein the thermosetting powder coating composition further comprises: E: one or more inhibitors selected from the group consisting of phenolic compounds, stable radicals, catechols, phenothiazines, hydroquinones, benzoquinones and mixtures thereof, wherein the total amount of component E is at least 20 and at most 1500 mg/Kg A and B.

56. The thermosetting powder coating composition according to claim 55, wherein the UR is an unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations.

57. The thermosetting powder coating composition according to claim 56, wherein the unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations has: a) a number average molecular weight (M.sub.n) of at least 1000 and at most 10000 Da, and b) a glass transition temperature (T.sub.g) of at least 40 and at most 75° C., and c) a weight per unsaturation (WPU) of at least 250 and at most 2200 g/mol, and wherein the M.sub.n is measured via Gel Permeation Chromatography (GPC), the T.sub.g is measured via Differential Scanning calorimetry (DSC), and the WPU is measured via .sup.1H-NMR spectroscopy.

58. The thermosetting powder coating composition according to claim 57, wherein the dilauroyl peroxide is present in an amount of at least 40 mmol/Kg A and B.

59. The thermosetting powder coating composition according to claim 57, wherein the total amount of the component C is at most 250 mmol/Kg A and B.

60. The thermosetting powder coating composition according to claim 59, wherein B is present in an amount of at least 15 and at most 55 pph of A and B.

61. The thermosetting powder coating composition according to claim 60, wherein the onium compounds of component D are selected from the group consisting of compounds represented by the following formula I-X and compounds represented by the following formula II-X: ##STR00048## wherein A.sup.− is selected from the group consisting of halide anions; and R.sub.1′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl, and R.sub.2′″ is a C.sub.1-C.sub.12 saturated hydrocarbyl.

62. The thermosetting powder coating composition according to claim 61, wherein the curing agent A which is selected from the group consisting of i), ii) and iii): i) one or more crystalline VU-c each of which is a crystalline vinyl urethane having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the one or more crystalline VU-c are in the region of from and including 45 up to and including 78° C., and a number average molecular weight (M.sub.n) of at least 660 and at most 1200 Da, and ii) one or more crystalline VFUR-c each of which is a crystalline vinyl functionalized urethane resin having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the one or more crystalline VFUR-c are in the region of from and including 45 up to and including 78° C., and a number average molecular weight (M.sub.n) of at least 660 and at most 1200 Da, and iii) mixtures of the one or more crystalline VU-c and the one or more crystalline VFUR-c, wherein the M.sub.n is measured via Gel Permeation Chromatography (GPC).

63. The thermosetting powder coating composition according to claim 62, wherein the curing agent A is one or more crystalline VU-c, and wherein each VU-c is a crystalline VEU-c, wherein VEU-c is a crystalline vinyl ether urethane having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the crystalline VEU-c are in the region of from and including 30 up to and including 80° C.

64. The thermosetting powder coating composition according to claim 62, wherein the curing agent A is selected from the group consisting of diethylene glycol divinyl ether urethane, triethylene glycol divinyl ether urethane, and mixtures thereof.

65. The thermosetting powder coating composition according to claim 61, wherein the curing agent A is one or more crystalline VU-c, and wherein each VU-c is a crystalline VEU-c, wherein VEU-c is a crystalline vinyl ether urethane having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the crystalline VEU-c are in the region of from and including 30 up to and including 80° C.

66. The thermosetting powder coating composition according to claim 61, wherein the curing agent A is selected from the group consisting of diethylene glycol divinyl ether urethane, triethylene glycol divinyl ether urethane, and mixtures thereof.

67. The thermosetting powder coating composition according to claim 57, wherein the total amount of the component C is at most 190 mmol/Kg A and B.

68. The thermosetting powder coating composition according to claim 1, wherein the UR is an unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations.

69. The thermosetting powder coating composition according to claim 1, wherein the UR has: a) a number average molecular weight (M.sub.n) of at least 1000 and at most 10000 Da, and b) a glass transition temperature (T.sub.g) of at least 40 and at most 75° C., and c) a weight per unsaturation (WPU) of at least 250 and at most 2200 g/mol, and wherein the M.sub.n is measured via Gel Permeation Chromatography (GPC), the T.sub.g is measured via Differential Scanning calorimetry (DSC), and the WPU is measured via .sup.1H-NMR spectroscopy.

70. The thermosetting powder coating composition according to claim 1, wherein the curing agent A which is selected from the group consisting of i), ii) and iii): i) one or more crystalline VU-c each of which is a crystalline vinyl urethane having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the one or more crystalline VU-c are in the region of from and including 45 up to and including 78° C., and a number average molecular weight (M.sub.n) of at least 660 and at most 1200 Da, and ii) one or more crystalline VFUR-c each of which is a crystalline vinyl functionalized urethane resin having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the one or more crystalline VFUR-c are in the region of from and including 45 up to and including 78° C., and a number molecular weight weight (M.sub.n) of at least 660 and at most 1200 Da, and iii) mixtures of the one or more crystalline VU-c and the one or more crystalline VFUR-c, wherein the M.sub.n is measured via Gel Permeation Chromatography (GPC).

71. The thermosetting powder coating composition according to claim 1, wherein the curing agent A is one or more crystalline VEU-c, wherein VEU-c is a crystalline vinyl ether urethane having a melting enthalpy ΔH.sub.m≥35 J/g, and one or more melting temperatures (T.sub.m) wherein any and all of the T.sub.m of the crystalline VEU-c are in the region of from and including 30 up to and including 80° C.

72. The thermosetting powder coating composition according to claim 1, wherein the curing agent A is selected from the group consisting of diethylene glycol divinyl ether urethane, triethylene glycol divinyl ether urethane, and mixtures thereof.

73. The thermosetting powder coating composition according to claim 1, wherein the thermosetting powder coating composition has a glass transition temperature (T.sub.g) of at least 25 and at most 70° C., wherein the T.sub.g is measured via Differential Scanning calorimetry (DSC).

74. The thermosetting powder coating composition according to claim 1, wherein the curing agent A has a T.sub.c which is at most 55° C. lower than the T.sub.m of the curing agent A, or if the curing agent A has more than one T.sub.m then the curing agent A has a T.sub.c which is lower than a highest T.sub.m of the curing agent A.

75. A process for making the thermosetting powder coating composition as defined in claim 1, wherein the process comprises the steps of: (a) mixing the components of the thermosetting powder coating composition to obtain a premix; (b) heating the premix in an extruder up to and including the decomposition temperature of the component C, to obtain an extrudate; (c) cooling down the extrudate to obtain a solidified extrudate; and (d) grinding the solidified extrudate into smaller particles to obtain the thermosetting powder coating composition.

76. A thermosetting powder coating composition as defined in claim 1 which is cured.

77. An article having a cured coating thereon, wherein the cured coating comprises the thermosetting powder coating composition as defined in claim 76.

78. An article having coated thereon the thermosetting powder coating composition as defined in claim 1.

79. A process for making a coated article, wherein the process comprises the steps of: (a) applying the thermosetting powder coating composition as defined in claim 1 to an article, and (b) heating and/or radiating the thermosetting powder coating composition for enough time and at a suitable temperature to cure the thermosetting powder coating composition and thereby obtain the coated article.

Description

EXAMPLES

(1) The invention is explained in more detail with reference to the following non-limiting examples.

(2) In the Examples section, the abbreviation UR represents unsaturated resin comprising ethylenic unsaturations, the abbreviation VU represents vinyl urethanes, the abbreviation VFUR represents vinyl functionalized urethane resins used as curing agents, the abbreviation PCC represents thermosetting powder coating composition and the abbreviation PC represents powder coating. In all the examples the unsaturated resins comprising ethylenic unsaturations (UR) were unsaturated polyester resins comprising 2-butenedioic acid ethylenic unsaturations.

(3) All powder coating compositions presented in the Examples were thermosetting powder coating compositions (TPCC).

(4) In the Examples section the abbreviation ‘Comp’ denotes a Comparative Example of either a thermosetting powder coating composition e.g. CompPCC1, or a powder coating e.g. CompPC1. In the Examples section the abbreviation ‘Inv’ denotes an Inventive Example of a thermosetting powder coating composition e.g. InvPCC1, or a powder coating e.g. InvPC1.

(5) In this section (Examples), any method for the measurement of a parameter for a UR is meant to equally apply for any acrylic resin, polyurethane, epoxy resin, polyamide, polyesteramide, polycarbonate, polyurea and polyester resin e.g. for an unsaturated polyester resin, for an unsaturated polyester resin comprising ethylenic unsaturations such as an acrylated polyester resin, unsaturated polyester resin comprising di-acid ethylenic unsaturations, for an unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations, that a UR may be selected from.

(6) In this section (Examples), any method for the measurement of a parameter for a VU is meant to equally apply for any VU such as any crystalline VU-c e.g. any crystalline VEU-c, any crystalline VESU-c, any crystalline VEESU-c.

(7) In this section (Examples), any method for the measurement of a parameter for a VFUR is meant to equally apply for any VFUR such as any crystalline VFUR-c e.g. such as any crystalline VEFUR-c e.g. any crystalline VESFUR-c, any crystalline VEESFUR-c.

(8) Any reference to paragraph numbers mentioned in the Examples section, refers to paragraphs mentioned in the Examples section.

(9) 1. Chemicals, Raw Materials; Analytical Methods and Techniques

(10) 1.1 Chemicals & Raw Materials

(11) Laurox®-S (supplied by AkzoNobel Polymer Chemicals), is a solid mixture of dilauroyl peroxide (peranhydride) and water wherein the amount of dilauroyl peroxide is 99% w/w on the solid mixture; water is the carrier material for the dilauroyl peroxide.

(12) Perkadox® 24-FL (supplied by AkzoNobel Polymer Chemicals), is a solid mixture of dicetyl peroxydicarbonate and water wherein the amount of dicetyl peroxydicarbonate is 94.5% w/w on the solid mixture; water is the carrier material for the dicetyl peroxydicarbonate.

(13) Perkadox® 26 (supplied by AkzoNobel Polymer Chemicals), is a solid mixture of dimyristyl peroxydicarbonate and water wherein the amount of dimyristyl peroxydicarbonate is 94.5% w/w on the solid mixture; water is the carrier material for the dimyristyl peroxydicarbonate.

(14) Perkadox® 16 (supplied by AkzoNobel Polymer Chemicals), is a solid mixture of di(4-tert-butylcyclohexyl) peroxydicarbonate and water wherein the amount of di(4-tert-butylcyclohexyl) peroxydicarbonate is 95.5% w/w on the solid mixture; water is the carrier material for the di(4-tert-butylcyclohexyl) peroxydicarbonate.

(15) Perkadox® PM-W75 (supplied by AkzoNobel Polymer Chemicals), is a solid mixture of bis(4-methylbenzoyl) peroxide (peranhydride) and water wherein the amount of bis(4-methylbenzoyl) peroxide is 75% w/w on the solid mixture; water is the carrier material for bis(4-methylbenzoyl) peroxide.

(16) Trigonox® C-50D PD (supplied by AkzoNobel Polymer Chemicals) is a solid mixture of t-butyl peroxybenzoate (perester) and silicium oxide wherein the amount of t-butyl peroxybenzoate is 50% w/w on the solid mixture; silicium oxide is the carrier material for the t-butyl peroxybenzoate.

(17) Trigonox® EHP (supplied by AkzoNobel Polymer Chemicals), is a liquid mixture of di(2-ethylhexyl) peroxydicarbonate (peroxydicarbonate) and water wherein the amount od di(2-ethylhexyl) peroxydicarbonate is 98% w/w on the liquid mixture; water is the carrier material for di(2-ethylhexyl) peroxydicarbonateperoxydicarbonate. Trigonox® EHP is a peroxydicarbobate.

(18) Trigonox® 23 (supplied by AkzoNobel Polymer Chemicals), is a liquid mixture of tert-butyl peroxyneodecanoate (perester) and water wherein the amount tert-Butyl peroxyneodecanoate is 95% w/w on the liquid mixture; water is the carrier material tert-Butyl peroxyneodecanoate. Trigonox® 23 is a perester.

(19) Trigonox® 423 C70 (supplied by AkzoNobel Polymer Chemicals), is a liquid mixture of 1,1,3,3-tetramethylbutyl peroxyneodecanoate (perester) and OMS (=odorless mineral spirits), wherein the amount tert-1,1,3,3-tetramethylbutyl peroxyneodecanoate is 70% w/w on the liquid mixture; water is the carrier material 1,1,3,3-tetramethylbutyl peroxyneodecanoate.

(20) Cobalt stearate (solid, purity of 98%) (supplied by Alfa Aesar) was used a transition metal compound.

(21) Kronos® 2360 (supplied by Kronos Titan GmbH) is titanium dioxide and was used as a white pigment.

(22) t-Butyl hydroquinone (supplied by Sigma-Aldrich) was used as an inhibitor.

(23) Resiflow® PV-5 (supplied by Worlée-Chemie GmbH) was used as a flow control agent.

(24) Diphenyliodoniumchloride (supplied by Sigma-Aldrich) is an onium compound and it reads on formula II-X.

(25) Diethylene glycol monovinylether (liquid; purity 99%) was supplied by BASF.

(26) Triethylene glycol monovinylether (liquid; purity 99%) was supplied by BASF.

(27) 4-hydroxybutyl vinylether (liquid; purity 99%) was supplied by BASF.

(28) Any other chemicals mentioned in the Examples and not explicitly mentioned in this paragraph, were supplied by Aldrich and they were used as supplied.

(29) 1.2 Analytical Methods and Techniques

(30) The methods described 1.2.1-1.2.6 for the measurement of properties disclosed herein for a UR applies analogously for any UR that may form part of component A as disclosed in the entire application, e.g. acrylic resin, polyurethane, epoxy resin, polyamide, polyesteramide, polycarbonate, polyurea and polyester resin e.g. for an unsaturated polyester resin, for an unsaturated polyester resin comprising ethylenic unsaturations such as an acrylated polyester resin, unsaturated polyester resin comprising di-acid ethylenic unsaturations, for an unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations.

(31) The methods described 1.2.1-1.2.6 for the measurement of properties disclosed herein for a VFUR applies analogously for any VFUR that may form part of component B as disclosed in the entire application, e.g. a crystalline VFUR-c such as a crystalline VEFUR-c, a crystalline VESFUR-c, a crystalline VEESFUR-c.

(32) The methods described 1.2.1-1.2.6 for the measurement of properties disclosed herein for a VU applies analogously for any VU that may form part of the component B as disclosed in the entire application, e.g. a crystalline VU-c such as a crystalline VEU-c, a crystalline VESU-c, a crystalline VEESU-c.

(33) The methods described 1.2.6, 1.2.8 and 1.2.9 for the measurement of properties disclosed herein for a TPCC of the invention applies analogously for any TPCC of the invention as disclosed in the entire application.

(34) 1.2.1 Method for Measuring the Number Average Molecular Weight (M.sub.n) (Herein Abbreviated as ‘GPC Method’)

(35) The number average molecular weight (M.sub.n) was measured via Gel Permeation Chromatography (GPC) calibrated with a set of polystyrene standards (type EASICAL PS1 and 2 from Agilent) with a molecular weight range of from 500 up to 2.5×10.sup.6 g/mol and using as eluent a mixture of tetrahydrofuran (THF) 99.92% and 0.08% acetic acid, at a flow rate of 1 mL eluent/minute at 40° C. More specifically, 40 mg of a sample of for example UR or VU or VFUR—as the case may be—, were dissolved in 700 μL NMP (N-methyl-pyrrolidone) for 20 minutes at 100° C. The solution thus produced was subsequently cooled down to 25° C., and 5 mL of eluent were added to the solution. 40 μL of the solution thus prepared were injected into the pre-column (as this is described below) for the GPC measurement to be carried out. The GPC measurements were carried out on a Waters Alliance HPLC system equipped with: i) a Waters Alliance 2414 refractive index detector at 40° C., and ii) a Waters Alliance 2695 separation module equipped with a pre-column of mixed-C type, PLgel 5 μm Guard, 50×7.5 mm (PL1110-1520 from Agilent) and two consecutive PL-gel columns of Mixed-C type with l/d=300/7.5 mm (PL1110-6500 from Agilent), and filled with particles having a particle size of 5 μm (supplied by the Polymer Laboratories) and c) software for analyzing the obtained chromatograph and measuring the M.sub.n.

(36) 1.2.2 Method for Measuring the Melt Viscosity

(37) Melt viscosity (herein mentioned as viscosity, in Pa.Math.s) measurements were carried out at 160° C. on a Brookfield CAP 2000+ H Viscometer. The applied shear-rate was 70 s.sup.−1 and a 19.05 mm spindle (cone spindle CAP-S-05 (19.05 mm, 1.8°) was used.

(38) 1.2.3 Method for Measuring the Acid Value (AV)

(39) The acid value (AV) was measured according to ISO 2114. The AV is given as the mass of potassium hydroxide (KOH) in milligrams that is required to neutralize one gram of the tested substance and is used as a measure of the concentration of carboxylic acid groups present.

(40) 1.2.4 Method for Measuring the Hydroxyl Value (OHV)

(41) The hydroxyl value (OHV) was measured according to ISO 4629. The OHV is given as the mass of potassium hydroxide (KOH) in milligrams that is required to neutralize one gram of the tested substance and is used as a measure of the concentration of hydroxyl groups present.

(42) 1.2.5 Method for Measuring the WPU (Herein Abbreviated as ‘.sup.1H-NMR Method WPU’)

(43) The WPU was measured via .sup.1H-NMR spectroscopy according to the method entitled—for simplicity—‘.sup.1H-NMR method WPU’ which is presented herein. The estimated margin of error of this method for determining the WPU is +1-2%; the margin of error was determined on the basis of measuring three samples of the same lot of a UR or a VFUR or a VU.

(44) More specifically, said WPU was measured via .sup.1H-NMR spectroscopy as explained herein after and it was calculated according to the following equation EX2:

(45) $\begin{array}{cc}\mathrm{WPU}={\left[\frac{W_{\mathrm{pyr}}}{W_{\mathrm{resin}}}\frac{1}{{\mathrm{MW}}_{\mathrm{pyr}}}\frac{A_{c=c}\text{/}{N}_{c=c}}{A_{\mathrm{pyr}}\text{/}{N}_{\mathrm{pyr}}}\right]}^{-1}& \left(\mathrm{EX2}\right)\end{array}$
wherein,
W.sub.pyr is the weight of pyrazine (internal standard),
W.sub.resin is the weight of UR such as an unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations, or the weight of a curing agent such as a VFUR or a VU; W.sub.pyr and W.sub.resin are expressed in the same units.
MW.sub.pyr is the molecular weight of the pyrazine (=80 Da) (internal standard).
A.sub.pyr is the peak area for methine protons attached to the aromatic ring of pyrazine and
N.sub.pyr is the number of the methine protons of pyrazine (=4).

(46) In case of a UR:

(47) A.sub.C═C is the peak area for methine protons ( . . . —CH═ . . . ) of the ethylenic unsaturations (>C═C<) of the UR; N.sub.C═C is the number of methine protons ( . . . —CH═ . . . ) attached to the ethylenic unsaturations (>C═C<) of the UR.

(48) In case of a VFUR or a VU—as the case may be—:

(49) A.sub.C═C is the peak area for the methine proton ( . . . —CH═ . . . ) of the vinyl groups ( . . . —CH═CH.sub.2) in the VFUR or in the VU—as the case may be—; N.sub.C═C is the number of methine protons ( . . . —CH═ . . . ) of the vinyl groups ( . . . —CH═CH.sub.2) in the VFUR or in the VU—as the case may be—.

(50) The peak areas of the methine protons of pyrazine and methine protons ( . . . —CH═ . . . ) of the ethylenic unsaturations (>C═C<) of the UR in EX2 were measured as follows: A sample of 75 mg of UR was diluted at 25° C. in 1 ml deuterated chloroform containing a known amount (mg) of pyrazine as internal standard for performing .sup.1H-NMR spectroscopy. Subsequently, the .sup.1H-NMR spectrum of the UR sample was recorded at 25° C. on a 400 MHz BRUKER NMR-spectrometer. Afterwards, the chemical shifts (ppm) of the methine protons of pyrazine and the methine protons ( . . . —CH═ . . . ) of the ethylenic unsaturations (>C═C<) of the UR were identified; the chemical shifts (ppm) of the methine protons of pyrazine and the methine protons ( . . . —CH═ . . . ) of the ethylenic unsaturations (>C═C<) of the UR in EX2 measured on a 400 MHz BRUKER NMR-spectrometer in methanol and deuterated chloroform were at about 8.6 and at about 6.4-6.9 ppm, respectively. Subsequently, with the help of suitable commercially available software for analyzing .sup.1H-NMR spectra such as ACD/Spectrus Processor software provided by ACD/Labs, the peak areas of the methine protons of pyrazine and methine protons ( . . . —CH═ . . . ) of the ethylenic unsaturations (>C═C<) of the UR of EX2 were measured and from these values the WPU was determined according to EX2.

(51) If 75 mg of a UR is not soluble at 25° C. in 1 ml of deuterated chloroform, then any other suitable solvent or mixture of solvents known to the skilled person for performing the .sup.1H-NMR spectroscopy may be used; for example DMSO (dimethyl sulfoxide), pyridine, tetra-chloro ethane, and mixtures thereof. The choice of a suitable solvent or a mixture of suitable solvents depends on the solubility of the sample of the UR in said solvents. If 75 mg of UR is soluble in 1 mL of deuterated chloroform at 25° C., then deuterated chloroform is the solvent of choice for performing the .sup.1H-NMR spectroscopy for the UR. If a different solvent or mixture of solvents is used for performing the .sup.1H-NMR Method WPU, then the chemical shifts of the protons of EX2 may shift from the ones reported here for the selected solvents for the .sup.1H-NMR Method WPU since the actual chemical shifts may depend on the solvent or mixture of solvents used to record the .sup.1H-NMR spectrum; in such case one should identify and determine the chemical shifts of the corresponding protons and apply EX2 for the determination of WPU.

(52) The peak areas of the methine protons of pyrazine and methine protons ( . . . —CH═ . . . ) of the vinyl groups ( . . . —CH═CH.sub.2) in the VFUR or in the VU of EX2—as the case may be—were measured as follows: A sample of 75 mg of VFUR or VU—as the case may be—was diluted at 40° C. in a mixture of 0.200 ml methanol and 0.600 ml deuterated chloroform containing a known amount (mg) of pyrazine as internal standard for performing .sup.1H-NMR spectroscopy. Subsequently, the .sup.1H-NMR spectrum of the VFUR or the VU sample—as the case may be—was recorded at 40° C. on a 400 MHz BRUKER NMR-spectrometer. Afterwards, the chemical shifts (ppm) of the methine protons of pyrazine and the methine protons ( . . . —CH═ . . . ) of the vinyl groups ( . . . —CH═CH.sub.2) in the VFUR or in the VU—as the case may be—were identified; the chemical shifts (ppm) of the methine protons of pyrazine and methine protons ( . . . —CH═ . . . ) of the vinyl groups ( . . . —CH═CH.sub.2) in the VFUR or in the VU of EX2—as the case may be—were measured on a 400 MHz BRUKER NMR-spectrometer in methanol and deuterated chloroform were at about 8.6 and at about 6.4-6.5 ppm, respectively. Subsequently, with the help of suitable commercially available software for analyzing .sup.1H-NMR spectra such as ACD/Spectrus Processor software provided by ACD/Labs, the peak areas of the methine protons of pyrazine and methine protons ( . . . —CH═ . . . ) of the vinyl groups ( . . . —CH═CH.sub.2) in the VFUR or in the VU of EX2—as the case may be—were measured and from these values the WPU was determined according to EX2.

(53) If 75 mg of a VFUR or a VU—as the case may be—, are not soluble at 40° C. in a mixture of 0.200 ml methanol and 0.600 ml deuterated chloroform, then any other suitable solvent or mixture of solvents known to the skilled person for performing the .sup.1H-NMR spectroscopy may be used; for example DMSO (dimethyl sulfoxide), pyridine, tetra-chloro ethane, and mixtures thereof. The choice of a suitable solvent or a mixture of suitable solvents depends on the solubility of the sample of the VFUR or a VU—as the case may be—, in said solvents. If 75 mg of VFUR or VU—as the case may be—, are soluble in a mixture of 0.200 ml methanol and 0.600 ml deuterated chloroform at 40° C., then a mixture of methanol and deuterated chloroform is the solvent of choice for performing the .sup.1H-NMR spectroscopy for the VFUR or the VU.

(54) If a different solvent or mixture of solvents is used for performing the .sup.1H-NMR Method WPU, then the chemical shifts of the protons of EX2 may shift from the ones reported here for the selected solvents for the .sup.1H-NMR Method WPU since the actual chemical shifts may depend on the solvent or mixture of solvents used to record the .sup.1H-NMR spectrum; in addition, one may perform the measurement at different temperature than the one disclosed herein, for example the measurement can be performed at higher temperature than the one disclosed herein in order to solubilize the sample intended to be analyzed for measuring its WPU according to this method and/or may use a lower amount of sample e.g. 25 mg, depending on the resolution of the NMR instrument; in such case one should identify and determine the chemical shifts of the corresponding protons and apply EX2 for the determination of WPU.

(55) The method—as described herein—for the measurement of the WPU of the samples mentioned in the Examples, applies analogously for any UR and any VFUR, VU, taking of course into account common general knowledge in performing and analyzing results of NMR spectroscopy, the particular chemical nature of the UR or the VFUR or the VU and the skills of one skilled in the art of NMR spectroscopy; for example, the chemical shifts may be somewhat shifted from the ones disclosed herein, and/or the temperatures used to perform the measurement different e.g. higher than the ones disclosed herein, or the amount of the sample used can be lower e.g. 25 mg, depending on the resolution of the NMR instrument; in such case one should identify and determine the chemical shifts of the corresponding protons and apply EX2 for the determination of WPU.

(56) 1.2.6 DSC Method for the Measurement of T.sub.g, T.sub.m, T.sub.c, ΔH.sub.m, ΔH.sub.c, (Herein Abbreviated as ‘DSC Method’)

(57) The glass transition temperature (T.sub.g in ° C.), the crystallization temperature (T.sub.c in ° C.), the crystallization enthalpy (ΔH.sub.c in J/g), the melting temperature (T.sub.m in ° C.), the melting enthalpy (ΔH.sub.m in J/g) were measured via Differential Scanning calorimetry (DSC) on a TA instruments DSC Q2000 apparatus equipped with a cooling system TA instruments RCS90, in N.sub.2 atmosphere calibrated with indium. The glass transition temperature, the crystallization temperature, the crystallization enthalpy, the melting temperature, the melting enthalpy, of a chemical entity described in this application—to the extent that these parameters were applicable for said entity—were measured at any time from 24 up to and including 72 hours from the time of the preparation of said chemical entity. The processing of the signal (DSC thermogramme, Heat Flow vs. Temperature) was carried out using Universal Analysis 2000 software version 4.5a provided by TA instruments, as described herein after:

(58) A sample of 10±0.5 mg was weight and placed in the DSC cell. The sample was cooled down to −20° C. and the temperature was kept at −20° C. for 1 minute; upon 1 minute the sample was heated up to 200° C. at a heating rate of 5° C./minute (thermograph A). Once the sample has reached 200° C., the temperature was maintained at 200° C. for 1 minute. Subsequently, the sample was cooled down to −90° C. at a cooling rate of 5° C./minute (thermograph B); once the sample has reached −90° C., the temperature was maintained at −90° C. for 1 minute. Subsequently, the sample was heated up to 150° C. at a heating rate of 5° C./minute (thermograph C) Thermographs A, B and C were processed as the Y axis of the thermographs representing the heat flow has exotherm up and endotherm down.

(59) Thermograph A was used for measuring the glass transition temperature of the thermosetting powder coating composition (T.sub.g TPCC).

(60) Thermograph C was used for measuring the glass transition temperature of the UR (T.sub.g UR).

(61) Thermograph C was used for measuring the glass transition temperature of the VFUR (T.sub.g VFUR).

(62) Thermograph C was used for measuring the ΔH.sub.m and T.sub.m.

(63) Thermograph B was used to measure the ΔH.sub.c, T.sub.c.

(64) The glass transition temperature was the midpoint temperature of the temperature range over which the glass transition took place, said midpoint temperature was the point at which the curve was intersected by a line that was equidistant between the two extrapolated baselines, as defined in § 3.2 and § 3.3 in ISO 11357-2 edition 1999-03-15 [for midpoint temperature see § 3.3.3 in ISO 11357-2; edition 1999-03-15].

(65) The T.sub.m was measured as the temperature recorded at the minimum heat flow of the endothermic signal attributed to the melting of the sample.

(66) The ΔH.sub.m was measured as the integrated heat flow over the temperature range of the melting.

(67) The T.sub.c was measured as the temperature recorded at the maximum heat flow of the exothermic signal attributed to the crystallization of the sample.

(68) The ΔH.sub.c was measured as the integrated heat flow over the temperature range of the crystallization.

(69) 1.2.7 Method to Determine Presence of Unreacted —N═C═O Groups (Free Isocyanate Groups) (Herein Abbreviated as ‘Method NCO’)

(70) An FT-IR spectrum was recorded on a Digilab Excalibur infrared spectrometer, using a Golden gate ATR accessory from Specac. FT-IR spectra were taken using a resolution of 4 cm.sup.−1, over a range of 700 cm.sup.−1 to 4000 cm.sup.−1 over 64 scans and processed with Varian Resolutions pro software version 5.1. A characteristic peak for unreacted —N═C═O groups can be found around 2250 cm.sup.−1; the presence of this peak is indicative of unreacted —N═C═O groups (free isocyanate groups).

(71) 1.2.8 Measurement and Assessment of the Physical Storage Stability of the Thermosetting Powder Coating Compositions

(72) The physical storage stability (PSS) of the thermosetting powder coating compositions of the invention was tested at 23° C. for 7 weeks (for results see Table 3). Prior to assessing the PSS the thermosetting powder coating composition was left to cool down to room temperature for about 2-3 hours. The greater the extend of agglomeration or sintering the poorer the PSS, thus the lower its ranking according to the following scale. The extent of agglomeration was visually assessed and ranked according to the following rating on a 1-10 scale (1 representing the worst PSS and 10 the best PSS):

(73) 10: No change.

(74) 9: No agglomeration, very good fluidity.

(75) 8: No agglomeration, good fluidity.

(76) 7: Very low agglomeration; agglomeration can be dispersed by one light tap into a fine powder.

(77) 6: Very low agglomeration; agglomeration can be dispersed by several taps into a fine powder.

(78) 5: Low agglomeration; agglomeration can be dispersed by hand pressure into a fine powder.

(79) 4: Low agglomeration; agglomeration cannot be dispersed by hand pressure in a fine powder.

(80) 3: Severe agglomeration into several large lumps, material is pourable.

(81) 2: Severe agglomeration into several large lumps, material is not pourable.

(82) 1: product sintered to one lump, volume reduced.

(83) 1.2.9 Assessment of the Ability of a Thermosetting Powder Coating Composition to Heat-Cure Fast at Low Temperature

(84) The assessment of the ability of a thermosetting powder coating composition to heat-cure fast at low temperature was performed preparing a powder coating of said thermosetting powder coating composition according to § 4 in the Examples (‘Preparation of the powder coatings’) and then measuring the acetone double rubs that the thus prepared powder coating withstood. If the powder coating was able to withstand 210 ADR, then the corresponding thermosetting powder coating composition was able to heat-cure fast at low temperature (this is indicated as a ‘yes’ in the corresponding examples). If the powder coating was not able to withstand 210 ADR, then the corresponding thermosetting powder coating composition was not able to heat-cure fast at low temperature (this is indicated as a ‘no’ in the corresponding examples).

(85) 1.2.10 Methods for the Measurement of Properties of the Powder Coatings Obtained by Heat-Curing of the Thermosetting Powder Coating Compositions Prepared Herein

(86) The properties of the any and all of the powder coatings obtained by heat-curing of their corresponding thermosetting powder coating compositions were (and are to be) measured on the MDF substrates that they were applied on (see also ‘Preparation of the powder coatings’). Any and all properties of the powder coatings e.g. acetone double rubs (ADR), smoothness, coating (film) thickness, shown in the Exmaples, were assessed upon heat-curing the corresponding thermosetting powder coating compositions (applied on MDF substrates) at low temperature, that is upon heat-curing at 95° C. for 3 minutes in a catalytic IR oven. The type of MDF substrates used was of Medite-MR type.

(87) 1.2.10.1 Smoothness

(88) Smoothness (or also known in the art as flow) of powder coatings obtained by heat cure of the corresponding thermosetting powder coating compositions, was determined by comparing the smoothness of the coating with PCI Powder Coating Smoothness panels (ACT Test Panels Inc., APR22163 (A) Batch: 50708816) at a thickness of 100-120 μm. The rating of smoothness is from 1 to 10, with 1 representing the roughest coating and 10 representing the smoothest coating. By a rating of ‘<1’ is meant that the smoothness of the powder coating was lower than the powder coating smoothness panel with the lowest smoothness that of 1; effectively a powder coating with a smoothness <1 is a very rough powder coating.

(89) 1.2.10.2 Coating (Film) Thickness

(90) The coating (film) thickness of the powder coatings derived upon heat curing of the corresponding thermosetting powder coating compositions, was measured with a Elcometer 195 Saberg Drill from Elcometer according to EN ISO 2808-5B:2007; the measurement was carried out on a coated surface of the coated MDF panel. The film thickness of any one of powder coatings shown in the Examples and the Tables was in the range of from 100 up to 120 μm; any and all properties measured herein concerning powder coatings should be measured at this film thickness range.

(91) 1.2.10.3 Acetone Double Rubs (ADR)

(92) With one acetone double rub (ADR) is meant one continuous back and forward movement, in a cycle time of about one second, over the surface of a powder coating having a thickness of 100-120 μm using a cotton cloth drenched in acetone, which cotton cloth covers a hammer head having a weight of about 980 grams and a contact surface area with the powder coating of about 2 cm.sup.2. Every 10 rubs the cloth was drenched in acetone. The measurement was carried out at room temperature, and it was performed on coatings that were left at room temperature for 24-48 hours before been tested; the measurement was continued either until the coating was removed and the number of ADR at which the coating was removed was reported, or until 500 ADR were reached. A result reported as 500 ADR indicates that there was coating left after 500 ADR.

(93) 2. Synthesis of UR and Curing Agents

(94) 2.1 Synthesis of Unsaturated Resins Comprising Ethylenic Unsaturations (UR)

(95) Table 1 presents the monomers used for the preparation of the unsaturated resins comprising ethylenic unsaturations said resins being amorphous unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations and the properties of said resins.

(96) Amorphous (UR1-UR3) unsaturated polyesters comprising 2-butenedioic acid ethylenic unsaturations were prepared.

(97) All unsaturated polyester resins comprising 2-butenedioic acid ethylenic unsaturations (UR1-UR3) prepared herein were solid at room temperature and at atmospheric pressure.

(98) UR1

(99) A reactor vessel fitted with a thermometer, a stirrer and a distillation device for the removal of water formed during the synthesis, was filled with a tin catalyst (butyl stannoic acid, 1 g) and the monomers for the first step (isophthalic acid (320.1 g; 1.93 mol), neopentylglycol (314.5 g; 3.02 mol) and hydrogenated bisphenol A (270.1 g; 1.12 mol) as listed in Table 1). Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to 220° C.; the temperature was kept at 220° C. till no water was released. Subsequently, the reaction mixture was cooled down to 180° C.; once the temperature reached 180° C. fumaric acid (231.6 g; 2.0 mol) together with a small amount of t-butyl hydroquinone (0.2 g; 0.0012 mol) was added at a temperature of 180° C. followed by esterification at 205° C. (second step). When an acid value of less than 15 mg KOH/g resin was reached and water stopped being released, the third step of the polyester preparation was carried out under reduced pressure at 205° C. till an acid value of 6.5 mg KOH/g was reached. In order to lower the acid value of the resin below 5 mgKOH/g resin, 2,3-epoxy propyl neodecanoate (7.7 g; 0.03 mol) was added to the resin in order to react with the acid groups of the resin; upon the addition of 2,3-epoxy propyl neodecanoate the reaction continued for at least 30 minutes. Subsequently, the polyester resin was discharged onto an aluminum foil kept at room temperature. The polyester resin obtained had an acid value of 4.7 mgKOH/g resin and a hydroxyl value of 35.7 mgKOH/g resin.

(100) UR2

(101) A reactor vessel fitted with a thermometer, a stirrer and a distillation device for the removal of water formed during the synthesis, was filled with a tin catalyst (butyl stanoic acid, 1 g) and the monomers for the first step (terephthalic acid (553.7 g; 3.33 mol), trimethylol propane (44.1 g; 0.33 mol) and neopentyl glycol (443.4 g; 4.26 mol) as listed in Table 1). Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to 220° C.; the temperature was kept at 220° C. till no water was released. Subsequently, the reaction mixture was cooled down to 180° C.; once the temperature reached 180° C. fumaric acid (112.5 g; 0.92 mol) together with a small amount t-butyl hydroquinone (0.1 g; 0.0006 mol) was added at a temperature of 180° C. followed by esterification at 205° C. (second step). When an acid value of less than 15 mg KOH/g resin was reached and water stopped being released, the third step of the polyester preparation was carried out under reduced pressure at 205° C. till an acid value of 6.5 mg KOH/g was reached. In order to lower the acid value of the resin below 5 mgKOH/g resin, ethylene carbonate (5.6 g; 0.06 mol) was added to the resin in order to react with the acid groups of the resin; upon the addition of ethylene carbonate the reaction continued for at least 30 minutes. Subsequently, the polyester resin was discharged onto an aluminum foil kept at room temperature. The polyester resin obtained had an acid value of 3.1 mgKOH/g resin and a hydroxyl value of 42.7 mgKOH/g resin.

(102) UR3

(103) A reactor vessel fitted with a thermometer, a stirrer and a distillation device for the removal of water formed during the synthesis, was filled with a tin catalyst (butyl stannoic acid, 1 g) and the monomers for the first step (terephthalic acid (422 g; 2.54 mol), 1,2-propylene glycol (354.6 g; 4.66 mol), benzoic acid (92.8 g; 0.76 mol) and trimethylol propane (18.8 g; 0.14 mol) as listed in Table 1). Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to 220° C.; the temperature was kept at 220° C. till no water was released. Subsequently, the reaction mixture was cooled down to 180° C.; once the temperature reached 180° C. fumaric acid (220.5 g; 1.9 mol) together with a small amount of t-butyl hydroquinone (0.1 g; 0.0006 mol) was added at a temperature of 180° C. followed by esterification at 205° C. (second step). When an acid value of less than 15 mg KOH/g resin was reached and water stopped being released, the third step of the polyester preparation was carried out under reduced pressure at 205° C. till an acid value of 6.5 mg KOH/g was reached. Subsequently, the polyester resin was discharged onto an aluminum foil kept at room temperature. The polyester resin obtained had an acid value of 1 mgKOH/g resin and a hydroxyl value of 52.6 mgKOH/g resin.

(104) 2.2 Synthesis of the Curing Agents

(105) Vinyl functionalized urethane resins (VFUR) and vinyl urethanes (VU) were prepared and they were used as curing agents in the thermosetting powder coating compositions prepared herein.

(106) Table 2 presents the monomers used for the preparation of VFUR1, VFUR2, VU1, VU2 and VU3 and their properties.

(107) Each of the VFUR1, VFUR2 was a crystalline vinyl ether functionalized urethane resin (crystalline VEFUR).

(108) VU1 was a crystalline vinyl ether urethane (crystalline VEU).

(109) VU2 was a crystalline VEU-c; more particularly VU2 was diethylene glycol divinyl ether urethane.

(110) VU3 was a crystalline VEU-c; more particularly VU3 was triethylene glycol divinyl ether urethane.

(111) Each of VFUR1, VFUR2, VU1, VU2 and VU3 was crystalline, because each of them had a ΔHm≥35 J/g.

(112) The VFUR1 is not a curing agent A because it did not have any and all of its melting temperatures within the T.sub.m range of 30-80° C. The VFUR1 had two melting temperatures, one at 98 and one at 107° C., thus both of them were outside the T.sub.m range of 30-80° C.

(113) The VFUR2 is not a curing agent A because it did not have any and all of its melting temperatures within the T.sub.m range of 30-80° C. The VFUR2 had two melting temperatures, one at 74 and one at 84° C., thus one of them was outside the T.sub.m range of 30-80° C.

(114) The VU1 is not a curing agent A because it did not have any and all of its melting temperatures within the T.sub.m range of 30-80° C. The VU1 had a melting temperature at 100° C., which was outside the T.sub.m range of 30-80° C.

(115) The VU2 is a curing agent A because it did have any and all of its melting temperatures within the T.sub.m range of 30-80° C. The VU2 had two melting temperatures, one at 69 and one at 76° C., thus any and all of its T.sub.m was within the T.sub.m range of 30-80° C.

(116) The VU3 is a curing agent A because it did have any and all of its melting temperatures within the T.sub.m range of 30-80° C. The VU3 had one melting temperature at 56° C., thus any and all of its T.sub.m was within the T.sub.m range of 30-80° C.

(117) VFUR1

(118) A reaction vessel fitted with a thermometer and a stirrer, was filled with the monomers for the first step as listed in Table 2. Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to approximately 60° C. Subsequently, for the second step an isocyanate as listed in Table 2 was dosed such that the reaction mixture was kept below 120° C. during addition. After all isocyanate was dosed, the temperature was kept or set at 120° C. and maintained at this temperature for approximately half an hour. The temperature was kept at 120° C. and vacuum was applied to remove all volatiles. After vacuum the content of the vessel was discharged.

(119) VFUR2

(120) A reaction vessel fitted with a thermometer, a stirrer and a distillation device for the removal of water formed during the synthesis, was filled with a tin catalyst (butyl stannoic acid, 0.5 g) and the monomers for the first step (except 4-hydroxybutyl vinyl ether) as listed in Table 2. Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to 220° C. The temperature was kept at 220° C. till an acid value of approximately 10 mg KOH/g resin was reached and till no water was being released. Subsequently, the temperature was lowered to 120° C. and as last monomer of the first step the 4-hydroxybutyl vinyl ether and a tin catalyst (dibutyltin dilaurate, 0.5 g) were added at a temperature of 120° C. Subsequently, for the second step the isocyanate as listed in Table 2 was dosed such that the reaction mixture was kept below 120° C. during addition. After all the isocyanate was dosed, the temperature was kept or set at 120° C. and maintained at this temperature for approximately half an hour. The temperature was kept at 120° C. and vacuum was applied to remove all volatiles. After vacuum the content of the vessel was discharged.

(121) VU1

(122) A reaction vessel fitted with a thermometer and a stirrer, was filled with the monomers for the first step as listed in Table 2. Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to approximately 60° C. Subsequently, for the second step an isocyanate as listed in Table 2 was dosed such that the reaction mixture was kept below 120° C. during addition. After all isocyanate was dosed, the temperature was kept or set at 120° C. and maintained at this temperature for approximately half an hour. The temperature was kept at 120° C. and vacuum was applied for half an hour to remove all volatiles. Subsequently, n-butanol was added until there were no unreactable isocyanate groups as evidenced by using the Method NCO, described herein. At 120° C. a vacuum was applied for half an hour to remove any residual n-butanol. After this period the content of the vessel was discharged.

(123) VU2

(124) A reaction vessel fitted with a thermometer and a stirrer, was filled with the monomers for the first step as listed in Table 2. Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to approximately 60° C. Subsequently, for the second step an isocyanate as listed in table 2 was dosed such that the reaction mixture was kept below 100° C. during addition. After all isocyanate was dosed, the temperature was kept or set at 90° C. and maintained at this temperature for approximately half an hour. The temperature was kept at 90° C. until there were no unreactable isocyanate groups as evidenced by using the Method NCO, described herein and then vacuum was applied for half an hour to remove all volatiles. After this period the content of the vessel was discharged.

(125) VU3

(126) A reaction vessel fitted with a thermometer and a stirrer, was filled with the monomers for the first step as listed in Table 2. Stirring was then applied and a light nitrogen flow was passed over the reaction mixture while the temperature was raised to approximately 60° C. Subsequently, for the second step an isocyanate as listed in table 2 was dosed such that the reaction mixture was kept below 100° C. during addition. After all isocyanate was dosed, the temperature was kept or set at 80° C. and maintained at this temperature for approximately half an hour. The temperature was kept at 80° C. until there were no unreactable isocyanate groups as evidenced by using the Method NCO, described herein and then vacuum was applied for half an hour to remove all volatiles. After this period the content of the vessel was discharged.

(127) 3. Preparation of the Thermosetting Powder Coating Compositions

(128) The preparation of the thermosetting powder coating compositions shown in the Examples and used for either the CompPCC or InvPCC was carried out as follows: First the unsaturated resin comprising ethylenic unsaturation (UR) and the vinyl urethane or the vinyl functionalized urethane resin—as the case may be—were mixed in a 90/10 ratio on weight (UR/VU or UR/VFUR as the case may be) in a blender; said mixture was subsequently extruded in a PRISM TSE16 PC twin screw extruder at 120° C. with a screw speed of 200 rpm and a torque higher than 90%. The obtained extrudate was allowed to cool to room temperature and broken into chips. Subsequently, the extrudate was placed in a blender, together with all other paint components, including any remaining VU or VFUR—as the case may be—, making the formulations as listed in the corresponding Tables; subsequently, the mixture obtained was extruded in a PRISM TSE16 PC twin screw extruder at 80° C. with a screw speed of 200 rpm and a torque higher than 50%. The extrudate was allowed to cool at room temperature and broken into chips. After approximately 12-16 hours these chips were then ground in an ultra-centrifugal mill at 14000 rpm and sieved in a Retsch ZM100 sieve. The sieve fraction with particle size below 90 μm was collected (by means of a Fritsch Analysette Spartan sieving apparatus equipped with a 90 micron sieve, sieving performed for 15 minutes at 2.5 mm amplitude) and used for further processing.

(129) Any one of the thermosetting powder coating compositions described in the Examples and shown in the relevant Tables, was white and had a particle size lower than 90 microns.

(130) Each of the thermosetting powder coating compositions according to the invention shown in the Examples (InvPCC) had a glass transition temperature (T.sub.g) of at least 25 and at most 70° C., wherein the T.sub.g was measured via Differential Scanning calorimetry (DSC) according to § 1.2.6.

(131) 4. Preparation of the Powder Coatings

(132) MDF substrates (type Medite-MR) were preheated at 60-70° C. using a gas catalytic IR oven from Vulcan. The thermosetting powder coating compositions CompPCC and InvPCC alike, prepared herein, were electrostatically sprayed (corona spray gun, 60 kV) onto the preheated MDF substrates once the latter were brought out from the oven; the temperature of MDF substrates during the electrostatic spraying was 50-60° C. Subsequently, the coated MDF substrates were cured at 95° C. for 3 minutes in a catalytic IR oven (Vulcan) (without the application of radiation), affording white powder coatings.

(133) TABLE-US-00001 TABLE 1 Composition and characterization of the unsaturated resins comprising ethylenic unsaturations (UR) (each of the UR was an unsaturated polyester resin comprising 2-butenedioic acid ethylenic unsaturations). UR1 UR2 UR3 Monomers first step Isophthalic acid (mol) 1.93 Terephthalic acid (mol) 3.33 2 54 Neopentylglycol (mol) 3.02 4 26 Trimethylol propane (mol) 0.33 0 14 1,2-propylene glycol (mol) 4 66 Benzoic acid 0.76 Hydrogenated bisphenol A (mol) 1.12 Monomers second step Fumaric acid (mol) 2 0.97 1.9 Total (mol) 8.07 8.89 10 Monomers first step Isophthalic acid (g) 320.1 Terephthalic acid (g) 553.7 631.6 Neopentylglycol (g) 314.5 443.4 Trimethylol propane (g) 44.1 45.1 1,2-propylene glycol (g) 362.2 Hydrogenated bisphenol A (g) 270.1 Monomers second step Fumaric acid (g) 231.6 112.5 114 Total weight (g) 1136.3 1153.7 1152.9 Water formed during synthesis (g) 136.3 153.7 152.9 Weight (g) of resin produced 1000 1000 1000 Properties & Characterisation amorphous amorphous amorphous WPU (g/mol) 536 1130 530 M.sub.n (Da) 3451 2798 3324 T.sub.g (° C.) 53 47 43.2 Viscosity (Pa .Math. s) @ 160° C. 41.1 21.2 4.0 AV (mg KOH/g UR) 4.7 3.1 6.5 OHV (mg KOH/g UR) 35.7 42.7 12.8

(134) TABLE-US-00002 TABLE 2 Composition and characterization of the vinyl functionalized urethanes resins (VFUR) and vinyl urethanes (VU) used as curing agents in the TPCC shown in the Examples. VFUR1 VFUR2 VU1 VU2 VU3 Monomers first step Hexane diol (mol) 0.32 Butane diol (mol) 0.05 4-Hydroxylbutyl vinyl ether (mol) 4.53 2.83 4.8 diethylene glycol monovinylether 4.64 triethylene glycol monovinylether 3.85 dodecane dioic acid 1.13 ethyleneglycol 1.79 Monomers second step Hexamethylene diisocyanate (mol) 2.58 1.77 2.58 2.3 1.9 Total (mol) 7.43 7.52 7.43 6.94 5.76 Total weight of reactants (g) 1000 1000 1000 1000 1000 Weight (g) of VFUR or VU produced 1000 1000 1000 1000 1000 Properties & Characterisation crystaline crystaline crystalline crystalline crystalline VEFUR VEFUR VEU VEU-c VEU-c WPU (g/mol) 207 328 183 197 239 M.sub.n (Da) 738 1053 656 685 818 T.sub.g (° C.) −59 — — — — T.sub.m (° C.) (first melting temperature) 98 74 100 69 56 T.sub.m (° C.) (second melting temperature) 107 84 — 76 — ΔH.sub.m (J/g) (associated to the first melting temperature) 170 102 165 35 141 ΔH.sub.m (J/g) (associated to the second melting temperature) 1.9 55 — 100 — ΔH.sub.m (J/g) (the sum of all All, associated to each of the 171.9 157 165 135 141 melting temperatures) T.sub.c (° C.) 84 61 77 48 25 ΔH.sub.c (J/g) 175 99 166 136 126 Viscosity (Pa .Math. s) @ 160° C. <0.1 <0.1 <0.1 <0.1 <0.1 AV (mg KOH/g VU) 0 0 0 0 0 OHV (mg KOH/g VU) 0 0 0 0 0

(135) TABLE-US-00003 TABLE 3 Composition and properties of comparative thermosetting powder coating compositions and powder coatings thereof. CompPCC1 CompPCC2 CompPCC3 CompPCC4 CompPCCS CompPCC6 CompPCC7 CompPCC3 CompPCC9 CompPCC10 CompPCC11 UR1 (g) 200 200 200 200 200 200 200 200 200 200 200 VFUR1 (g) 81.8 VU2 (g) 78.2 78.2 78.2 78.2 78.2 78.2 78.2 78.2 78.2 78.2 Perkadox ® PM-W75 (g) 15.1 10.1 Laurox ® S (g) 16.6 Trigonox ® EHP (g) 14.5 9.6 Trigonox ® 23 (g) 10.2 6.8 Trigonox ® 423 C70 (g) 11.9 17.9 Perkadox ® 24 FL (g) 16.7 Trigonox ® C 500 PD (g) 16.2 cobaltstearate (g) 0.87 diphenyliodonium chloride (g) 2.7 2.7 2.7 2.7 2.7 t-butylhydroquinone (g) 0.070 0.070 0.070 0.070 0.070 0.070 0.070 0.070 0.070 0.070 0.070 Kronos ® 2310 (g) 84.5 83.5 83.5 83.5 83.5 83.5 83.5 83.5 83.5 83.5 83.5 Resiflow ® PV-5 (g) 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 K 1.06 1.06 1.06 1.06 1.06 1,06 1.06 1.06 1.06 1.06 11 Amount of component C 99.8 150.8 100.8 149.9 150.2 99.4 150.3 100.2 98.0 99.6 149.8 (mmol/Kg A and B) Amount of component D 29.8 0.0 30.2 0.0 0.0 30.2 0.0 30.2 0.0 30.2 0.0 (mmol/Kg A and B) Amount of component E 250 250 250 250 250 250 250 250 250 250 250 (mg/Kg A and B) Properties of the the thermosetting powder coating compositions PSS 8 8 8 8 5 7 6 8 8 1 1 very good very good very good very good good very good good very good very good very poor very poor Able to heat-cure fast at low temperature no no no no no no no no no no no CompPC1 CompPC2 CompPC3 CompPC4 CompPC5 CompPC6 CompPC7 CompPC8 CompPC9 CompPC10 CompPC11 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed 10 15 17 77 17 139 12 35 42 8 63 upon heat curing at 95° C./3 minutes) very poor very poor very poor very poor very poor poor very poor very poor very poor very poor very poor Smoothness (PCI) (assessed upon heat <1 5 5 4 3 2 4 4 4 <1 1 curing at 95°C./3 minutes) poor sufficient sufficient sufficient sufficient sufficient sufficient sufficient sufficient poor poor

(136) TABLE-US-00004 TABLE 4 Composition and properties of comparative thermosetting powder coating compositions and powder coatings thereof. CompPCC12 CompPCC13 CompPCC14 CompPCC15 CompPCC16 UR1 (g) 200 200 200 UR2 (g) 200 UR3 (g) 200 VFUR1 (g) 81.8 81.8 VU1 (g) 41.4 82.8 VFUR2 (g) 133.1 Perkadox ® PM-W75 (g) 10.1 Perkadox ® 26 (g) 12.4 Perkadox ® 16 (g) 6.7 Perkadox ® 24 FL (g) 16.7 19.8 diphenyliodonium chloride (g) 2.7 2.7 3.2 t-butylhydroquinone (g) 0.070 0.070 0.083 0.060 0.071 Kronos ® 2310 (g) 84.5 84.5 99.9 72.4 84.8 Resiflow PV-5 (g) 4.2 4.2 5.0 3.6 4.2 K 1.20 1.20 1.09 1.13 1.06 Amount of component C (mmol/Kg A and B) 100 100 100 82 82 Amount of component D (mmol/Kg A and B) 29.8 29.8 29.9 0.0 0.0 Amount of component E (mg/Kg A and B) 250 250 250 250 250 Properties of the the thermosetting powder coating compositions PSS 8 8 8 2 3 very good very good very good poor mediocre Able to heat-cure fast at low temperature no no no no no CompPC12 CompPC13 CompPC14 CompPC15 CompPC16 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed upon heat 10 17 8 13 24 curing at 95° C./3 minutes) very poor very poor very poor very poor very poor Smoothness (PCI) (assessed upon heat curing at 1 0 0 0 1 95° C./3 minutes) poor poor poor poor poor

(137) TABLE-US-00005 TABLE 5 Composition and properties of comparative thermosetting powder coating compositions and powder coatings thereof. CompPCC17 CompPCC18 CompPCC19 UR1 (g) 200 200 200 VU2 (g) 78.2 78.2 78.2 Perkadox ® 24 FL (g) 4.2 4.2 diphenyliodonium chloride (g) 8.9 4.2 t-butylhydroquinone (g) 0.070 0.070 0.070 Kronosa ® 2310 (g) 83.5 83.5 83.5 Resiflow ® PV-5 (g) 4.2 4.2 4.2 K 1.07 1.07 1.07 Amount of component C (mmol/Kg A and B) 0 25 25 Amount of component D (nnmol/Kg A and B) 100 o 47 Amount of component E (mg/Kg A and B) 250 250 250 Properties of the the thermosetting powder coating compositions PSS 8 9 8 very good very good very good Able to heat-cure fast at low temperature no no no CompPC17 CompPC18 CompPC19 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed 23 12 27 upon heat curing at 95° C./3 minutes) very poor very poor very poor Smoothness (PCI) (asessed upon heat 7 5 3 curing at 95° C./3 minutes) sufficient sufficient sufficient

(138) TABLE-US-00006 TABLE 6 Composition and properties of comparative thermosetting powder coating compositions and powder coatings thereof. CompPCC20 CompPCC21 CompPCC22 CompPCC23 CompPCC24 CompPCC25 CompPCC26 CompPCC27 UR1 (g) 200 200 200 200 200 200 200 200 VFUR1 (g) 81.5 VU2 (g) 78.2 78.2 78.2 78.2 78.2 78.2 78.2 Laurox ® S (g) 11.2 5.5 22.3 16.6 22 2.8 11 diphenyliodonium chloride (g) 4.4 8.9 13.4 13.4 t-butylhydroquinone (g) 0.070 0.070 0.070 0.417 0.070 0.070 0.070 0.070 Kronos ® 2310 (g) 84.5 83.5 83.5 83.5 83.5 83.5 83.5 83.5 Resiflow ® PV-5 (g) 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 K 1.06 1.07 1.07 1.07 1.07 1.07 1.07 1.07 Amount of component C 100 0 50 201 150 199 25 99 (mmol/Kg A and B) Amount of component D 49 100 0 0 0 50 50 0 (mmol/Kg A and B) Amount of component E 250 250 250 1500 250 250 250 250 (mg/Kg A and B) Properties of the the thermosetting powder coating compositions PSS 8 8 8 7 7 6 8 8 very good very good very good very good very good good very good very good Able to heat-cure fast at low no no no no no no no yes temperature CompPC20 CompPC21 CompPC22 CompPC23 CompPC24 CompPC25 CompPC26 CompPC27 Properties of the corresponding powder coatings Chemical Resistance (ADR) 83 23 27 77 83 6 23 53 (assessed upon heat curing at 95° C./3 minutes) very poor very poor very poor very poor very poor very poor very poor very poor Smoothness (PCI) (assessed upon 1 7 3 8 4 1 4 3 heat curing at 95° C./3 minutes) poor sufficient sufficient sufficient sufficient poor sufficient sufficient

(139) TABLE-US-00007 TABLE 7 Composition and properties of inventive thermosetting powder coating compositions and powder coatings thereof. InvPCC1 InvPCC3 InvPCC4 InvPCC5 InvPCC6 InvPCC7 UR1 (g) 200 200 200 200 200 200 VU2 (g) 78.2 78.2 78.2 78.2 78.2 VU3 (g) 94.5 Laurox ® S (g) 5.5 11 11 11 11 11.7 diphenyliodonium chloride (g) 4.4 1.3 2.7 4.4 8.9 4.7 t-butylhydroquinone (g) 0.014 0.070 0.070 0.070 0.070 0.074 Kronos ® 2310 (g) 83.5 83.5 83.5 83.5 83.5 88.4 Resiflow ® PV-5 (g) 4.2 4.2 4.2 4.2 4.2 4.4 K 1.07 1.07 1.07 1.07 1.07 1.06 Amount of component C (mmol/Kg A and B) 50 99 99 99 99 100 Amount of component D (mmol/Kg A and B) 49 15 30 49 100 50 Amount of component E (mg/Kg A and B) 50 250 250 250 250 250 Properties of the the thermosetting powder coating compositions 8 8 8 8 8 7 PSS very good very good very good very good very good very good Able to heat-cure fast at low temperature yes yes yes yes yes yes InvPC1 InvPC3 InvPC4 InvPC5 InvPC6 InvPC7 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed 500 500 500 500 500 500 upon heat curing at 95° C./3 minutes) excellent excellent excellent excellent excellent excellent Smoothness (PCI) (assessed upon heat 4 3 3 3 2 3 curing at 95° C./3 minutes) sufficient sufficient sufficient sufficient sufficient sufficient

(140) TABLE-US-00008 TABLE 8 Composition and properties of comparative thermosetting powder coating compositions and powder coatings thereof. CompPCC28 CompPCC29 CompPCC30 CompPCC31 CompPCC32 UR1 (g) 200 200 200 200 200 VU3 (g) 94.5 94.5 94.5 94.5 94.5 Laurox ® 5(g) 2.9 31 11.7 11.7 11.7 diphenyliodoniumchloride (g) 4.7 4.7 33 0 0.2 t-butylhydroquinone (g) 0.074 0.074 0.074 0.074 0.074 Kronos ® 2310 (g) 88.4 88.4 88.4 88.4 88.4 Resiflow ® PV-5 (g) 4.4 4.4 4.4 4.4 4.4 K 1.06 1.06 1.06 1.06 1.06 Amount of component C (mmol/Kg A and B) 25 264 100 100 100 Amount of component D (mmol/Kg A and B) 50 50 349 0 2 Amount of component E (mg/Kg A and B) 250 250 250 250 250 Properties of the the thermosetting powder coating compositions PSS 9 5 4 7 7 very good good mediocre very good very good Able to heat-cure fast at low temperature no no no no no CompPC28 CompPC29 CompPC30 CompPC31 CompPC32 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed upon 15 58 40 33 68 heat curing at 95° C./3 minutes) very poor very poor very poor very poor very poor Smoothness (PCI) (assessed upon 4 3 <1 4 3 heat curing at 95° C./3 minutes) sufficient sufficient poor sufficient sufficient

(141) TABLE-US-00009 TABLE 9 Composition and properties of inventive thermosetting powder coating compositions and powder coatings thereof. InvPCC8 InvPCC9 InvPCC10 InvPCC11 InvPCC12 InvPCC13 UR1 (g) 200 200 200 200 200 200 VU3 (g) 94.5 94.5 94.5 94.5 94.5 94.5 Laurox ® 5 (g) 6 17.5 20.5 21.7 11.7 11.7 diphenyliodoniumchloride (g) 4.7 4.7 4.7 4.7 4.7 14.1 t-butylhydroquinone (g) 0.074 0.074 0.074 0.074 0.295 0.074 Kronos ® 2310 (g) 88.4 88.4 88.4 88.4 88.4 88.4 Resiflow ® PV-5 (g) 4.4 4.4 4.4 4.4 4.4 4.4 K 1.06 1.06 1.06 1.06 1.06 1.06 Amount of component C (mmol/Kg A and B) 51 149 175 185 100 100 Amount of component D (mmol/Kg A and B) 50 50 50 50 50 149 Amount of component E (mg/Kg A and B) 250 250 250 250 1000 250 Properties of the the thermosetting powder coating compositions PSS 9 8 7 7 8 7 very good very good very good very good very good excellent Able to heat-cure fast at low temperature yes yes yes yes yes yes InvPC8 InvPC9 InvPC10 InvPC11 InvPC12 InvPC13 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed upon heat 500 500 500 500 500 500 curing at 95° C./3 minutes) excellent excellent excellent excellent excellent excellent Smoothness (PCI) (assessed upon heat curing at 4 3 3 3 4 2 95° C./3 minutes) sufficient sufficient sufficient sufficient sufficient sufficient

(142) TABLE-US-00010 TABLE 10 Composition and properties of inventive thermosetting powder coating compositions and powder coatings thereof. InvPCC14 InvPCC15 InvPCC16 InvPCC17 InvPCC18 UR1 (g) 200 200 200 200 200 VFUR2 (g) 10 VU3 (g) 82 62 116 94.5 94.5 Laurox ® S (g) 11.7 10.6 12.5 11.7 11.7 diphenyliodoniumchloride (g) 4.7 4.2 5.1 4.7 1.5 t-butylhydroquinone (g) 0.073 0.066 0.079 0.074 0.074 Kronos ® 2310 (g) 87.6 78.6 94.8 88.4 88.4 Resiflow ® PV-5 (g) 4.4 3.9 4.7 4.4 4.4 K 1.05 0.70 1.30 1.06 1.06 Amount of component C (mmol/Kg A and B) 101 102 99 100 100 Amount of component D (mmol/Kg A and B) 50 50 50 50 16 Amount of component E (mg/Kg A and B) 250 250 250 250 250 Properties of the the thermosetting powder coating compositions PSS 8 8 8 8 8 very good very good very good very good very good Able to heat-cure fast at low temperature yes yes yes yes yes InvPC14 InvPC15 InvPC16 InvPC17 InvPC18 Properties of the corresponding powder coatings Chemical Resistance (ADR) (assessed upon heat 500 500 500 500 500 curing at 95° C./3 minutes) excellent excellent excellent excellent excellent Smoothness (PCI) (assessed upon heat 2 2 4 3 4 curing at 95° C./3 minutes) sufficient sufficient sufficient sufficient sufficient

(143) Only the Inventive Examples (thermosetting powder coating compositions according to the invention of claim 1; also referred as inventive TPCC) had in combination all features of claim 1. It was surprisingly found that only the inventive TPCC were able to provide for a unique combination of much desired properties. More specifically, only the inventive TPCC were heat curable and were able to heat-cure fast at low temperature and said heat curable thermosetting powder coating compositions upon heat-curing at low temperature were able to produce powder coatings having at least good, preferably very good, more preferably excellent chemical resistance. Actually, all the inventive TPCC were heat curable and were able to heat-cure fast at low temperature and said heat curable thermosetting powder coating compositions upon heat-curing at low temperature were able to produce powder coatings having excellent chemical resistance. Thus, only the inventive TPCC met the primary object of the invention.

(144) In addition, only the inventive TPCC were heat curable and were able to heat-cure fast at low temperature, had very good physical storage stability and said heat curable thermosetting powder coating compositions upon heat-curing at low temperature were able to produce powder coatings having at least good, preferably very good, more preferably excellent chemical resistance. Furthermore, only the inventive TPCC were heat curable and were able to heat-cure fast at low temperature, had very good physical storage stability, and said heat curable thermosetting powder coating compositions upon heat-curing at low temperature were able to produce powder coatings having: i) excellent chemical resistance, and ii) at least sufficient smoothness.

(145) None of the Comparative Examples had in combination all features of claim 1. Any and all Comparative Examples failed even to meet the primary object of the invention, let alone the additional surprising array of very desirable as explained and shown in this application.

(146) The invention of claim 1 constitutes a noticeable progress over the prior art and it contributes a great deal to the advancement and progress of the technology of thermosetting powder coatings. The reason being the invention of claim 1 makes feasible the achievement of heat curable thermosetting powder coating compositions that were able to heat-cure fast at low temperature and said heat curable thermosetting powder coating compositions upon heat-curing at low temperature were able to produce powder coatings having at least good, preferably very good, more preferably excellent chemical resistance. Actually, all the inventive TPCC were heat curable and were able to heat-cure fast at low temperature and said heat curable thermosetting powder coating compositions upon heat-curing at low temperature were able to produce powder coatings having excellent chemical resistance. In addition the inventive thermosetting powder coating compositions were able at the same time to achieve a further fantastic and unique array of very desirable properties as explained and shown in this application.