Valve disposition and configuration designed to improve color dosing response time in a process of coloring polyurethane products

摘要

This invention relates to an improved procedure and apparatus for making colored polyurethane foam products, such as carpet underlay and the like, as well as the improved colored product itself. Such a procedure entails the utilization of at least one valve assembly within a color dosing manifold such that the valve itself is simultaneously in contact with both the outside surface and the inside surface of the manifold. Such a disposition for a valve assembly permits color to be introduced directly into a binder (i.e., polyol and isocyanate) or polyol stream in order to substantially eliminate any color remaining in contact solely with the inside walls of the manifold. This in turn permits thorough mixing of the binder and colorant and substantially reduces the response time from opening the valve to producing colored polyurethane materials (such as polyurethane foam), thereby effectively eliminating the production of waste polyurethane product. The inventive configuration comprising a specific type of ball valve and/or the placement of a plurality of such disposed valves in a radial configuration on the manifold are also contemplated within the invention.