Patent ID: 11946582
Assignee: KNAUF INSULATION SPRL
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC F  C  D  E | IPC C  D  E  F

Claim 18:
19. A method of manufacturing a stone wool insulation product comprising sequentially:
forming stone wool fibers from a molten mineral mixture;
spraying a substantially formaldehyde-free, aqueous binder solution which comprises at least 5% solids and less than 20% solids onto the stone wool fibers just after they have been formed so that residual heat of the stone wool fibers causes water in the aqueous binder solution to evaporate;
collecting the stone wool fibers to which the binder solution has been applied to form a batt of stone wool fibers; and
curing the batt comprising the stone wool fibers and the binder by passing the batt through at least one zone of a curing oven at a temperature within the range 230° C.-300° C. with an oven residence time in the range 30 seconds to 20 minutes so as to provide a batt of stone wool fibers held together by a cured, thermoset, substantially formaldehyde-free, substantially water insoluble, nitrogenous polymer-containing binder;, to produce a stone wool insulation product which:, i) comprises less than 99% by weight and more than 80% by weight stone wool fibers; and, ii) has a density greater than 15 kg/m3 and less than 220 kg/m3; and, iii) a quantity of binder greater than 1% and less than 15% by dry weight;, and wherein the aqueous binder solution sprayed onto the stone wool fibers comprises (i) a carbohydrate reactant comprising a reducing sugar or a carbohydrate reactant that yields a reducing sugar in situ under thermal curing conditions and (ii) at least 5% by dry weight of an acid precursor in the aqueous solution, wherein the acid precursor comprises a) oxygen and b) at least one of sulphur, phosphorus and nitrogen;, and wherein the reaction of the binder upon curing is essentially a Maillard type reaction.