| 摘要 |
A process for producing various kinds of flexible polyurethane foams with different properties, comprising: bringing at least a polyol, a polyisocyanate and a blowing agent to contact with each other by employing a single production apparatus, wherein the polyisocyanate contains tolylene diisocyanate, and the polyol consists essentially of two or three types of polyols, at least two of these two or three types of polyols being selected from the group consisting of three types of polyoxyalkylene polyether polyols having an overall degree of unsaturation of less than 0.06 meq/g and three types of polymer polyols obtained from polyoxyalkylene polyether polyols having an overall degree of unsaturation of less than 0.06 meq/g; and wherein the two or three types of polyols, the polyisocyanate and the blowing agent are mixed at a mixing ratio varied to attain various changes of the values of the properties, thus flexible polyurethane foams with desired properties being obtainable. In particular, the use of a polyisocyanate containing tolylene diisocyanate in an amount of 20% by weight or more enables to change a core density of the flexible polyurethane foam in the range of 20 to 70 kg/m<3 >and to change a 25% ILD hardness of the flexible polyurethane foam in the range of 50 to 400 N/314 cm<2>. In the process for producing flexible polyurethane foams of the present invention, various kinds of flexible polyurethane foams having a wide range of values of properties such as hardness, density and impact resilience so as to meet requirements of a wide range of values of properties can be produced from essentially two or three types of polyols by employing a single production apparatus in a simple manner.
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