POLYISOCYANATE COMPOSITION FOR SOFT POLYURETHANE FOAM AND METHOD OF MANUFACTURING SOFT POLYURETHANE FOAM USING THE COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide a soft polyurethane foam having good storage stability, and having both of good air permeability and improved bottom-touch feeling when sitting on it, which are usually incompatible with each other.;SOLUTION: The polyisocyanate composition for soft polyurethane foam formed by urethanating a pure MDI (a) with an equivalent or less amount of a polyol (b), then mixing a polymeric MDI (c) in it, under the conditions shown below. The conditions are (2,2'-MDI+2,4'-MDI)/MDI=60-90 mass%, MDI/((a)+(c))=50-90 mass%, (b-1):(b-2)=(20-40) mass%:(80-60) mass%; provided that, (b-1) is a polyetherpolyol having an Mn of 1,000-10,000, the average number of functional groups is 2-8, oxyethylene group in repeating units is 70 mol% or more; and (b-2) is a polyetherpolyol having an Mn of 1,000-10,000, the average number of functional groups is 2-8, and the oxypropylene group in the repeating units accounts for 80 mol% or more.;COPYRIGHT: (C)2009,JPO&INPIT