| CPC C09K 21/04 (2013.01) [B27K 3/166 (2013.01); B27N 1/02 (2013.01); B27N 3/002 (2013.01); B27N 3/02 (2013.01); B27N 3/04 (2013.01); B27N 7/00 (2013.01); B27K 2200/15 (2013.01); B27K 2240/30 (2013.01)] | 6 Claims |

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1. A method for fireproofing or flameproofing wood composite boards selected from the group including medium or high density fiber boards or particle boards, during production of the boards, in which wood fibers or wood particles are passed from a storage and to a press via a blow line, and wherein a binder is added to the wood fibers or wood particles by mixing the binder into the fiber or particles by injecting, spraying or blending the binder into fiber or particle mix, in the blow line, resin blending or resin mixing chamber, and subsequently pressing the blend in a press to obtain the final wood composite board, and wherein the method further comprises adding a flame-retardant composition to the wood fibers or wood particles, by
a. injecting a liquid aqueous flame-retardant and latent hardener composition comprising a blend of diammonium hydrogen phosphate (DAP) and monoammonium dihydrogen phosphate (MAP),
wherein the blend of DAP and MAP in weight ratios ranges from 95% DAP/5% MAP to 60% DAP/40% MAP, and from 0.1 up to 15% by weight of total solids of one or more acids selected from the group consisting of organic acid, C2-C7 organic acid, citric acid, formic acid, acetic acid, malic acid, tartaric acid, oxalic acid, lactic acid, butyric acid, strong acid, hydrochloric acid, and any mixtures thereof, the liquid composition being an aqueous composition comprising a liquid aqueous solution of the contents ranging from 25% w/w to 80% w/w of the blend, to the blow line that passes the wood fibers or wood particles from the storage and to the press, and where the liquid aqueous flame-retardant composition is added to the blow line in parallel to the binder, or
b. adding a solid blend of the flame-retardant and latent hardener composition comprising a blend of DAP and MAP, wherein the blend of DAP and MAP in weight ratios ranges from 95% DAP/5% MAP to 60% DAP/40% MAP, and from 0.1 up to 15% by weight of total solids of one or more acids selected from the group consisting of organic acid, C2-C7 organic acid, citric acid, formic acid, acetic acid, malic acid, tartaric acid, oxalic acid, lactic acid, butyric acid, strong acid, hydrochloric acid, and any mixtures thereof, to the wood fibers or wood particles, parallel to the binder, in an intermediate mixing step provided between a refiner and the forming and hot-pressing steps in board production.
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