ACOUSTIC POLYMER-SAWING PLATE AND A METHOD OF ITS MAKING Russian patent published in 1995 - IPC

FIELD: acoustic article manufacture. SUBSTANCE: plate has carboxymethylcellulose as binder and paraffin as hydrophobic addition. Filler: wood saw-dust and chips of fraction 5 mm and less and portland cement as water-repellent addition for filler at the following ratio of components, technical carboxymethylcellulose 8-9; wood saw-dust 12.0-15.6; wood chips passed through the sieve with cell 5 mm 12.4-14.8; portland cement 2.8-4.0; kaolin 0.6-0.8; paraffin 0.6-0.8, and water 56.2-62.4. For acoustic plate making filler as wood saw-dust and wood chips of fraction 5 mm and less is impregnated preliminary with cement milk. The latter consists of portland cement and water at the ratio 1:3. Forming mass is prepared by mixing three early prepared components wood saw-dust and chips treated with cement milk, glue made of technical carboxymethylcellulose and aqueous suspension of kaolin followed by addition of melted paraffin. Ratio of components is given above. EFFECT: improved method of preparing. 3 cl, 2 tbl