摘要:
A process is described for the successive production of at least two non-cellular molded articles differing in their mechanical properties. Both articles are based on organic polyisocyanates which are trimerized in the presence of compounds which are reactive with isocyanate groups where the equivalent ratio of NCO groups to groups reactive with NCO groups is varied within the range of 1:0.8 to 1:0. In a second embodiment, a uniform article is produced having anisotropic mechanical characteristics varying continuously and/or stepwise.
摘要:
The present invention relates to a process for the production of moldings based on organic polyisocyanates which have short in-mold times. The polyisocyanates are subjected to a polymerization reaction in closed molds in the presence of trimerization catalysts. The process is preferably carried out in the presence of compounds containing isocyanate-reactive groups where the equivalent ratio between NCO and NCO-reactive groups is greater than 1:0.8. The process has to be carried out in the absence of blowing agents, in order to produce nonfoamed moldings.
摘要:
Polyurethane moldings having an inhomogeneously colored surface with color contrasts in fiber-like distribution are made by incorporating colored fibers of a specified type in a polyurethane forming reactionmixture. The colored fibers must have a staple length of from 0.1 to 6 mm, a denier of from 0.1 to 25 dtex, and a coloring agent that does not migrate or dissolve in the polyurethane-forming materials. These fibers are generally used in a quantity such that they represent from 0.1 to 10 wt. % of the polyurethane-forming reaction mixture. Shoe soles, shoe heels, multiple layer soles and padded components are examples of moldings which may be produced in accordance with the present invention.