The present invention A) A1) a low molecular weight diisocyanate having a molar mass of 140 to 278 g/mol and A2) polyalkylene oxide having 2 or more OH functionality and A3) optionally further isocyanate-reactive components not belonging to A2) Isocyanate-functional prepolymer obtainable by reacting； B) water in an amount of at least 2% by weight, based on the total weight of the composition； C) heterocyclic 4-membered or 6-membered ring oligomers of low molecular weight diisocyanates optionally having a molar mass of 140 to 278 g/mol； D) optionally a catalyst； E) salts of weak acids, optionally the corresponding free acid having pKS values of ≥ 3.0 and ≤ 14.0 in water at 25° C. F) optionally a surfactant； G) optionally monohydric or polyhydric alcohols or polyols, and H) arbitrarily H1) a low molecular weight diisocyanate having a molar mass of 140 to 278 g/mol and/or a polyisocyanate prepared therefrom and having an isocyanate functionality of 2 to 6； H2) monofunctional polyalkylene oxide with an OH value of 10 to 250 and an ethylene oxide content of 50 to 100 mol% based on the total amount of oxyalkaline groups obtained Hydrophilic polyisocyanate obtainable by reacting A composition comprising a is provided, it relates to a method for producing a foamed, cured polyurethane foam. Isocyanate-containing components, in particular components A, C and H, as a whole, in each case, based on the total amount of isocyanate-containing components, in the range of 2% to 8% by weight of isocyanate content and 1.0 to 3.5 mol/kg of urethane groups Has a content. The invention also relates to foams produced in this way and to their use.본 발명은A) A1) 140 내지 278 g/mol의 몰 질량의 저분자량 디이소시아네이트와A2) 2 이상의 OH 관능가를 갖는 폴리알킬렌 옥시드 및A3) 임의로 A2)에 속하지 않는 추가의 이소시아네이트-반응성 성분을 반응시켜 수득 가능한 이소시아네이트-관능성 예비중합체；B) 조성물의 총 중량을 기준으로 적어도 2 중량%의 양의 물；C) 임의로 140 내지 278 g/mol의 몰 질량을 갖는 저분자량 디이소시아네이트의 헤테로시클릭 4-원 또는 6-원 고리 올리고머；D) 임의로 촉매；E) 임의로 상응하는 유리 산이 25 ℃ 물 중에서 ≥ 3.0 및 ≤ 14.0의 pKS 값을 갖는 약산의 염
