SOLAR REFLECTIVE COATINGS AND COATING SYSTEMS

• US 20100047620A1
• Filed: 10/28/2009
• Published: 02/25/2010
• Est. Priority Date: 02/05/2007
• Status: Active Grant

• Current Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Original Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Inventors: Vanier, Noel R., Polk, W. David, McQuown, Stephen G., Decker, Eldon L., Hellring, Stuart D., Minch, Britt A.
• Granted Patent: US 9,056,988 B2
• Time in Patent Office: Days
• US Class Current: 428/688
• CPC Class Codes: B05D 7/54 No clear coat specified
• CPC Class Codes: C08F 293/00 Macromolecular compounds obtained by polymerisation on to a macromolecule having groups capable of inducing the formation of new polymer chains bound exclusively at one or both ends of the starting macromolecule on to polymers modified by introduction of unsaturated end groups C08F290/02
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08K 5/0041 Optical brightening agents, organic pigments
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C09D 17/003 containing an organic pigment process features in the making of dye stuff preparations C09B67/00
• CPC Class Codes: C09D 5/004 Reflecting paints; Signal paints
• CPC Class Codes: C09D 7/41 Organic pigments; Organic dyes
• CPC Class Codes: C09D 7/45 Anti-settling agents
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: C09D 7/67 Particle size smaller than 100 nm
• CPC Class Codes: C09D 7/70 characterised by shape, e.g. fibres, flakes or microspheres

Abstract

Disclosed are infrared reflective coating compositions and cured coatings deposited on a substrate, as well as multi-component composite coating systems. The coating compositions include an infrared transparent pigment and an infrared reflective pigment.

Claims

1. A coating composition comprising:

(a) a film-forming resin;

(b) a colored and/or opaque infrared reflective pigment; and

(c) an infrared transparent pigment;

wherein the coating composition, when formed into a cured coating, exhibits;

(1) a total solar reflectance of at least 15% as measured in accordance with ASTM E 903-96; and

(2) an angle dependent color change of no more than 5 Δ

E units when compared to the color of a control coating.

2. The coating composition of claim 1, wherein the cured coating further exhibits an angle dependent CIELAB L* value of no more than 50 at an observation angle of 25°

.

3. The coating composition of claim 2, wherein the angle dependent CIELAB L* value is no more than 25.

4. The coating composition of claim 1, wherein the total solar reflectance is at least 25%.

5. The coating composition of claim 1, further comprising a pigment dispersant.

6. The coating composition of claim 5, wherein the pigment dispersant comprises a tri-block copolymer.

7. The coating composition of claim 6, wherein the tri-block copolymer comprises:

(a) a first segment comprising infrared transparent pigment affinic groups;

(b) a second segment comprising polar groups; and

(c) a third segment which is different from the first segment and the second segment.

8. The coating composition of claim 7, wherein the infrared transparent pigment affinic groups comprises aromatic groups.

9. The coating composition of claim 7, wherein the third segment is substantially non-polar and substantially free of infrared transparent pigment affinic groups.

10. The coating composition of claim 5, wherein the pigment dispersant has a polymer chain structure represent by the general formula:

φ

-(G)_p-(W)_q—

(Y)_s-T

wherein;

(a) G is a residue of at least one radically polymerizable ethylenically unsaturated monomer;

(b) W and Y are residues of at least one radically polymerizable ethylenically unsaturated monomer;

with W and Y being different from one another;

(c) φ

is a hydrophobic residue of or derived from an initiator and is free of a radically transferable group of the initiator;

(d) T is or is derived from the radically transferable group of the initiator; and

(e) p, q, and s are each individually selected such that the pigment dispersant has a number average molecular weight of at least 250.

11. The coating composition of claim 5, wherein the pigment dispersant comprises a tri-block copolymer comprising:

(i) a first block comprising an oxirane functional monomer reacted with a carboxylic acid;

(ii) a second block comprising (meth)acrylic acid alkyl esters; and

(iii) a third block comprising (meth)acrylic acid alkyl esters.

12. The coating composition of claim 1, wherein the infrared reflective pigment has a ratio of reflectivity in the near-infrared region to reflectivity in the visible region of greater than 1:

1.

13. The coating composition of claim 1, wherein the infrared reflective pigment comprises an interference pigment.

14. The coating composition of claim 1, wherein the infrared transparent pigment comprises an organic pigment.

15. The coating composition of claim 14, wherein the organic pigment comprises aromatic groups.

16. The coating composition of claim 15, wherein the organic pigment comprises a perylene-based pigment.

17. A coating composition comprising:

(a) a film-forming resin;

(b) a thin flake metal or metal alloy infrared reflective pigment;

(c) an infrared transparent pigment having a maximum haze of 10%; and

(d) a polymeric pigment dispersant.

18. The coating composition of claim 17, wherein the infrared reflective pigment comprises aluminum flake.

19. The coating composition of claim 17, wherein the infrared reflective pigment has a maximum width of no more than 15 microns.

20. The coating composition of claim 17, wherein the infrared transparent pigment has an average primary particle size of no more than 100 nanometers.

21. The coating composition of claim 17, wherein the infrared transparent pigment comprises a black perylene pigment.

22. The coating composition of claim 17, wherein the polymeric pigment dispersant comprises a tri-block copolymer comprising:

(i) a first segment comprising infrared transparent pigment affinic groups;

(ii) a second segment comprising polar groups; and

(iii) a third segment which is different from the first segment and the second segment.

23. The coating composition of claim 22, wherein the infrared transparent pigment affinic groups comprises aromatic groups.

24. The coating composition of claim 22, wherein the third segment is substantially non-polar and substantially free of infrared transparent pigment affinic groups.

25. The coating composition of claim 22, wherein the polymeric pigment dispersant has a polymer chain structure represent by the general formula:

φ

-(G)_p(W)_q—

(Y)_s-T

wherein;

(a) G is a residue of at least one radically polymerizable ethylenically unsaturated monomer;

(b) W and Y are residues of at least one radically polymerizable ethylenically unsaturated monomer;

with W and Y being different from one another;

(c) φ

is a hydrophobic residue of or derived from an initiator and is free of a radically transferable group of the initiator;

(d) T is or is derived from the radically transferable group of the initiator; and

(e) p, q, and s are each individually selected such that the pigment dispersant has a number average molecular weight of at least 250.

26. A multi-component composite coating comprising:

(a) a first coating exhibiting a CIELAB L* value of no more than 50 and a total solar reflectance of at least 15% as measured in accordance with ASTM E 903-96 and deposited from a composition comprising;

(i) a film-forming resin;

(ii) an infrared reflective pigment;

(iii) a infrared transparent pigment; and

(iv) a pigment dispersant; and

(b) a second coating deposited beneath at least a portion of the first coating, the second coating being deposited from a composition comprising;

(i) a film-forming resin;

(ii) an infrared reflective flake pigment; and

(iii) an infrared reflective inorganic oxide pigment.

27. The composite coating of claim 26, wherein the sum of (b)(ii) and (b)(iii) in the composition from which the second coating is deposited is no more than 10% by weight, based on the total solids weight of the composition.