US 12,104,072 B2
Paint with low light reflectivity
Ben Poul Jensen, Newhaven (GB); Fiona-Mairéad McKenna, Newhaven (GB); and William John Kristian Ludlam, Newhaven (GB)
Assigned to SURREY NANOSYSTEMS LIMITED, Newhaven (GB)
Appl. No. 16/646,521
Filed by SURREY NANOSYSTEMS LIMITED, Newhaven (GB)
PCT Filed Oct. 8, 2018, PCT No. PCT/GB2018/052870
§ 371(c)(1), (2) Date Mar. 11, 2020,
PCT Pub. No. WO2019/073210, PCT Pub. Date Apr. 18, 2019.
Claims priority of application No. 1716503 (GB), filed on Oct. 9, 2017.
Prior Publication US 2020/0270475 A1, Aug. 27, 2020
Int. Cl. C09D 131/04 (2006.01); B05D 1/02 (2006.01); B05D 3/04 (2006.01); B05D 3/14 (2006.01); B05D 5/06 (2006.01); C08K 3/04 (2006.01); C09D 7/20 (2018.01); C09D 7/61 (2018.01); F24S 70/20 (2018.01); G02B 1/111 (2015.01)
CPC C09D 131/04 (2013.01) [B05D 1/02 (2013.01); B05D 3/0486 (2013.01); B05D 3/148 (2013.01); B05D 5/06 (2013.01); C08K 3/04 (2013.01); C09D 7/20 (2018.01); C09D 7/61 (2018.01); F24S 70/20 (2018.05); G02B 1/111 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A method of coating a substrate, including the steps of:
(i) providing a suspension of a carbon black-based pigment and a binder in a solvent, wherein the ratio of pigment to binder is greater than 40 wt % and the pigment is uniformly dispersed in the solvent;
(ii) spray-coating the suspension onto the substrate with the majority of the solvent evaporating during the spray coating step to result in a porous coating of pigment and binder on the substrate; and
(iii) continuing step (ii) until the coating thickness is at least 30 micrometres;
wherein the pigment does not include any carbon nanotubes,
wherein the binder is polyvinyl acetate or a mixture of vinyl acetate, vinyl neodecanoate and (meth) acrylic acid esters or any binder containing a component of vinyl acetate functionality, or the binder is acrylic based, and
wherein the coating of pigment and binder on the substrate has a density of up to 0.75 gcm−3 so as to result in pores or cavities which act as optical traps to suppress light reflectance.