US 11,787,162 B2
Roofing underlayment
Gurpreet S. Sandhar, Langley City (CA); Kenneth Russell Robson, Langley City (CA); and Sahar Khedri, Langley City (CA)
Assigned to FT Synthetics Inc., Langley City (CA)
Appl. No. 17/297,856
Filed by FT SYNTHETICS INC., Langley City (CA)
PCT Filed Nov. 29, 2018, PCT No. PCT/CA2018/051526
§ 371(c)(1), (2) Date May 27, 2021,
PCT Pub. No. WO2020/107094, PCT Pub. Date Jun. 4, 2020.
Prior Publication US 2022/0016876 A1, Jan. 20, 2022
Int. Cl. B32B 27/12 (2006.01); B32B 5/02 (2006.01); B32B 27/34 (2006.01); B32B 27/20 (2006.01); B32B 27/32 (2006.01); B32B 7/12 (2006.01); E04D 12/00 (2006.01)
CPC B32B 27/12 (2013.01) [B32B 5/022 (2013.01); B32B 7/12 (2013.01); B32B 27/20 (2013.01); B32B 27/32 (2013.01); B32B 27/34 (2013.01); E04D 12/002 (2013.01); B32B 2250/03 (2013.01); B32B 2262/0253 (2013.01); B32B 2264/0214 (2013.01); B32B 2264/104 (2013.01); B32B 2264/1021 (2020.08); B32B 2264/1023 (2020.08); B32B 2307/718 (2013.01); B32B 2307/724 (2013.01); B32B 2307/728 (2013.01); B32B 2307/7265 (2013.01); B32B 2307/73 (2013.01); B32B 2307/732 (2013.01); B32B 2419/06 (2013.01)] 34 Claims
OG exemplary drawing
 
1. A roofing underlayment comprising:
(a) a first layer that is nonwoven, vapour-permeable, and has a hydrophobic surface, comprising a polymer or mixture of polymers, the first layer being an outer layer configured to contact an exterior roofing material;
(b) a second layer that is water vapour-permeable and a liquid water barrier, comprising a carrier resin and a breathability agent, and
(c) a third layer configured to contact a roofing deck, the third layer being nonwoven, hydrophilic and liquid water absorptive,
wherein the second layer between the third layer and the first layer;
wherein the third layer comprises a carrier resin and a hydrophilic agent;
wherein the carrier resin comprises a polyolefin;
wherein the hydrophilic agent comprises between 2 and 10 weight % of the third layer;
wherein the roofing underlayment has a water absorbency of at least 9 g/m2 in 10 minutes; and
wherein the roofing underlayment has a breathability of at least 10 perms when measured in accordance with standard test method ASTM E96; and
wherein the roofing underlayment has a surface wettability on its bottom surface such that a contact angle between the bottom surface and water decreases to 0° in less than 6 seconds, measured in accordance with standard test method ASTM D724.