| 摘要 |
Process for manufacturing of molded objects by hot-pressing lignocellulose-containing materials with polyisocyanates as binders while using an agent to release the molded article from the surface of the metal press used. A mixture of the organosilicon compounds is applied onto the surface of the cauls or molds which faces the material to be pressed, and cured at a temperature from 100 DEG to 200 DEG C., preferably in the presence of known curing catalysts. The mixture of organosilicon compounds comprising (a) 20 to 65 weight percent of a silicone resin of the general formula <IMAGE> in which R1 is a low molecular weight alkyl radical with 1 to 4 carbon atoms, a has a value of 1 to 1.7, b has a value of 0.3 to 1.0; (b) 30 to 65 weight percent of an alpha , omega -methylsiloxanediol with an average molecular weight of 1,000 to 20,000; (c) 5 to 15 weight percent of a silicate ester of the general formula <IMAGE> in which R2 is a low molecular weight hydrocarbon radical with 2 to 4 carbon atoms, c has a value of 2.1 to 4.0; wherein the sum of components (a), (b) and (c) amounts to 100. The release properties can be further improved if more closely defined polysiloxane block copolymers are used as internal release agents.
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