Abstract: Disclosed is a substrate for out-of-ground cultivation by using a substrate consisting of mineral fibers. The substrate according to the invention is of limited dimensions and is used for the cultivation phase corresponding to the development of seedlings. This substrate, being of generally parallelepipedic shape, exhibits on its lower face added feet or pedestals that project therefrom and isolate the substrate from the ground on which its rests. The substrate according to the invention makes it possible to improve cultivation conditions.

Abstract: A substrate for out-of-ground cultivation is made of a felt of mineral fibers obtained by continuous longitudinal compression, at a rate between 1.5 and 15, of a sheet of mineral fibers in which the fibers are arranged in layers or strata parallel to the upper and lower faces of this sheet. The compression takes place before the heat treatment of the sheet for setting the binder.

Abstract: In a process for the production of fibers from phenoplast resins of the resole type, the resin is treated with a cross-linking agent and is immediately thereafter introduced into a centrifuge bushing. The fibers extruded from the bushing are projected into the surrounding atmosphere which is heated so as to accelerate the drying of the fibers before they are collected. The heating is sufficient so that the fibers become solid and non-sticky prior to collecting.

Abstract: The invention relates to techniques for above-ground cultivation, and, more precisely, cultivation elements designated with the name of "substrate".The cultivation cubes according to the invention are comprised of mineral fibers that are interconnected and whose distribution is without preferred order, no matter what direction they are viewed from.The substrates according to the invention promote better colonization of the material by the roots.

Abstract: Substrates for soil-free culturing are formed from a felt of mineral fibres having a hydroretentivity gradient such that the hydroretentivity decreases in the direction of gravity. The hydroretentivity gradient may be brought about by a gradient in the fineness of the fibres such that the average diameter of the fibres increases in the direction of gravity or the density of the fibres.

Abstract: A liquid mixture containing a heat-expandable resin and a catalyst is cast onto a lower facing, which is heated from below to cause expansion of the mixture and hardening of its lower part. The upper surface of the expanding mixture is covered with an upper facing applied while that portion is still soft, and the composite formed thereby is introduced to a heated enclosure while the upper part remains soft. The thickness of the formed composite, and panels derived thereof, is calibrated or limited by opposed conveyors within said thermal enclosure, which limits the maximum expansion to a value less than the theoretical potential expansion of the foam, allowing hardening to be completed, and subsequent cutting of the composite into panels.

Abstract: An etherified melamine-formaldehyde resin is disclosed that has prolonged shelf life, comparatively low free formaldehyde content, and is especially adapted as a binder for glass fiber mats. The melamine-formaldehyde resin is prepared in several distinct stages including condensation in a basic aqueous solution, etherification by cooling and acidification, neutralization with triethanolamine, and final stabilization. The free formaldehyde content of the resin so produced can be adjusted by reacting it with urea.