	US 12,331,227 B2
	Solvent-borne polyurethane adhesives with high molecular weight, high OH content and low solution viscosity
Dirk Achten, Leverkusen (DE); Fabian Schuster, Leverkusen (DE); Ann-Christin Bijlard-Jung, Rösrath (DE); and Joerg Tillack, Solingen (DE)
Assigned to Covestro Deutschland AG, Leverkusen (DE)
Appl. No. 18/246,703
Filed by Covestro Deutschland AG, Leverkusen (DE)
PCT Filed Sep. 21, 2021, PCT No. PCT/EP2021/075843 § 371(c)(1), (2) Date Mar. 27, 2023, PCT Pub. No. WO2022/063731, PCT Pub. Date Mar. 31, 2022.
Claims priority of application No. 20198814 (EP), filed on Sep. 28, 2020.
Prior Publication US 2023/0407152 A1, Dec. 21, 2023
Int. Cl. C09J 175/06 (2006.01); C08G 18/08 (2006.01); C08G 18/32 (2006.01); C08G 18/42 (2006.01); C08G 18/66 (2006.01); C08G 18/72 (2006.01); C08G 18/73 (2006.01); C08G 18/75 (2006.01); C08K 5/5398 (2006.01); C09J 5/00 (2006.01); C09J 11/06 (2006.01); C09J 175/02 (2006.01)

CPC C09J 175/06 (2013.01) [C08G 18/0857 (2013.01); C08G 18/3206 (2013.01); C08G 18/42 (2013.01); C08G 18/664 (2013.01); C08G 18/722 (2013.01); C08G 18/73 (2013.01); C08G 18/755 (2013.01); C08K 5/5398 (2013.01); C09J 5/00 (2013.01); C09J 11/06 (2013.01); C09J 175/02 (2013.01); C09J 2475/00 (2013.01)]

13 Claims

1. An adhesive composition comprising a polyurethane polymer, a solvent and a co-solvent,

wherein

the polyurethane polymer is an internally and/or externally hydrophilized thermoplastic polyurethane having a mass average molecular weight Mw, as determined by gel permeation chromatography against polystyrene standards using N,N-dimethyl acetamide as eluent, of ≥50000 g/mol,

the solvent is a polar-aprotic solvent,

the co-solvent is selected from water, a primary alcohol having ≤10 carbon atoms, a vicinal diol or a mixture thereof,

the solvent and the co-solvent are present in such amounts that they form a homogenous mixture without formation of a second phase when combined together at 20° C.,

a hydroxyl group content is ≥1 weight-%, based on total weight of the composition,

a polyurethane polymer content is ≥10 weight-%, based on the total weight of the composition and

the composition forms a single continuous liquid phase.