Abstract: An annular device (20) for spraying a sizing composition onto mineral fibres (3) comprises at least one circuit (24, 26) for distributing the sizing composition and at least one spray nozzle (22) in fluid communication with the distribution circuit and arranged on the periphery of the annular spray device in order to spray the sizing composition onto the fibres that pass through the annular spray device defined by an axis of revolution (X-X). According to the invention, the sizing composition is a binder based on biosourced products, and at least one spray nozzle comprises a spray head (36) having a slot (50) through which the biosourced-product-based binder leaves the annular spray device, said slot having a rectangular cross-section such as to form a flat jet of biosourced-product-based binder.

Abstract: The invention relates to a method of controlling the level of corrosivity of an aqueous solution recovered during a process for producing a blanket of mineral fibers, comprising in particular the fiberizing and the coating of said fibers with a binder comprising a polyacid typically of the acrylic type, said aqueous solution being at least partly recycled into a zone in which said resin is prepared and/or a scrubbing zone of the production plant, said method being characterized in that the pH of the solution in the recycling circuit is maintained between minimum and maximum values by injecting into said circuit an agent for modifying said pH, such as a base, the quantity injected or the flow rate of the pH-modifying agent being adjusted directly according to the quantity or the flow rate of acid binder injected during the fiberizing process. The invention also relates to the device for implementing the method.

Abstract: The invention relates to a resin composition based on a urea-modified phenol-formaldehyde resole which has a formaldehyde/phenol molar ratio of 2 to 5, exhibiting a free formaldehyde content lower than or equal to 3 percent (by weight relative to the total weight of the composition), a free phenol content lower than or equal to 0.5 percent and a dilutability measured at 20° C., of at least 1000 percent and to a process for the preparation of this composition. This composition is characterized in that it contains an overcondensed resole obtained by the condensation of phenol, of formaldehyde, and optionally of urea in basic medium, until the product has a water dilutability at pH 9 that is lower than or equal to 2000 percent, or the product of neutralization of such as resole. The modification of an overcondensed phenolic resole by neutralization with boric acid according to the invention permits the dilutability of the resole to be increased.

Abstract: To improve the reduction in tensile strength due to aging as well as the recovery, a weak acid is applied to a glass fiber mat containing a phenolic condensation resin binder before the binder is hardened.

Abstract: A glue composition comprises a heat-hardenable resin, urea and possibly one or several glue additives, and is characterized by the presence of an additional gluing compound is polyol having a functionality of at least equal to three. This glue can be used for mineral fibers in the manufacture of insulation products having improved properties.