Fire-resistant wooden pressure board and the production method thereof

Abstract

A fire-resistant wooden pressure plate is formed by conducting a cold pressing of 2˜10 MPa to the uniformly mixed not less than 50 wt % of a wood-containing powder material and an additive. The additive may include metallic oxide, non-metallic oxide, hydrochloride, sulfate, phosphate, weak acid, and strong acid. With class-A fire resistance, in-water rotting resistance, class-0 mold resistance, little or no detectable formaldehyde, some products described herein can replace traditional plates incapable of resisting fire in the following fields: 1. wooden veneer, wooden door, furniture, kitchenware, etc.; 2. wooden wall, base course, ground foundation, suspended ceiling, etc.; 3. wooden flooring; 4. wooden fire-resistant door, fire-resistant wall, etc.; 5. wooden house, wooden bench, wooden bulletin plate, wooden billboard, walkway paving, etc.; 6. wood handicrafts, toys, etc.

Claims

1. A fire-resistant wooden pressure plate, characterized in that the fire-resistant wooden pressure plate is formed by conducting a cold pressing of 2˜10 megapascals (MPa) to a uniform mixture of wood powder and an additive, wherein the wood powder is at a concentration of not less than 50 wt. %, and wherein the additive includes a metallic oxide, a non-metallic oxide, a hydrochloride, a sulfate, a phosphate, a weak acid, and a strong acid.

2. The fire-resistant wooden pressure plate according to claim 1, characterized in that the fire-resistant wooden pressure plate's density is 0.8˜4.6 g/cm.sup.3, and moisture content is 5˜25 wt %, and expansion rate of water absorption of 24 h is 5% or less, and static bending strength is 15˜50 MPa, and internal bond strength is 0.5˜8 MPa, and elastic modulus is 3000˜12000, and screw-holding force of board surface is 650˜2000 N.

3. The fire-resistant wooden pressure plate according to claim 2, characterized in that the fire-resistant wooden pressure plate's fireproof rating is class A, and the amount of released formaldehyde reaches the standard of ‘not detected’, and mold resistance rating reaches class 0.

4. A production method of fire-resistant wooden pressure plate, comprising: a. keeping a fineness of a raw material at 20˜100 mesh, and mixing it uniformly; b. laying boards; c. conducting pressing under normal temperature, with a pressure kept at 2˜10 MPa; d. maintaining the pressure for 12˜36 hours; and e. taking out the plate material and balancing it under normal temperature for 3˜10 days; wherein in operation step a., the raw material comprises a wood-chip powder at not less than 50 wt. % and an additive which includes a metallic oxide, a non-metallic oxide, a hydrochloride, a sulfate, a phosphate, a weak acid, and a strong acid, and wherein the additive is dispersed in water, and the additive liquid dispersion is used to wet the wood-chip powder, and uniformly-mixing the wetted material.

5. The production method of fire-resistant wooden pressure plate according to claim 4, characterized in that in operation b, the laying thickness of each board is 2˜15 cm, and pre-pressing thickness is 0.6˜7.5 cm.

6. The production method of fire-resistant wooden pressure plate according to claim 4, characterized in that in operation c, pressed object is a board-mold assembly having a plurality of repeating units composed of a pre-pressed plate and semifinished product piled up by flat plate mold.

7. The production method of fire-resistant wooden pressure plate according to claim 6, characterized in that the plate-mold assembly's height is 1˜2 m, and the height after pressing is 0.8˜1.2 m.

8. The production method of fire-resistant wooden pressure plate according to claim 6, characterized in that in operation c, the plate-mold assembly will be locked by mold-locking assembly after being pressed to specified thickness, then it will move out from pressing machine and go to the operation of maintaining pressure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a result table on the sound-insulation performance of a preferred embodiment of the present invention;

(2) FIG. 2 is a result table on the combustion performance of a preferred embodiment of the present invention;

(3) FIG. 3 is a result table on the bacteria resistance and the freezing and thawing resistance of a preferred embodiment of the present invention;

(4) FIG. 4 is a result table on the density, moisture content, etc. of a preferred embodiment of the present invention.

(5) FIG. 5 is a result table on the released formaldehyde of a preferred embodiment of the present invention;

(6) FIG. 6 is a result table on the board surface screw-holding force of a preferred embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

(7) 1. Material-mixing: 2480 KG of xylem fiber was weighed out, and the following additives were weighed out: 146 kg of magnesium oxide, 59 kg of magnesium chloride, 6 kg of silicon dioxide, 18 kg of calcium sulfate, 10 kg of calcium phosphate, 15 kg of acetic acid, and 20 kg of hydrochloric acid. The additives were dispersed in water to form a liquid dispersion with a certain concentration, then the uniformly-dispersed liquid dispersion was used to wet xylem fiber, and after uniform wetting, the uniformly-mixed material went into a material-spreading silo;

(8) 2. Material-spreading: The material-spreading thickness of each plate was 5 cm, and pre-pressing thickness was 2.2 cm, and weight was 45 kg˜47 kg, and the number of spread plates was 65, and the plate pile-up height was 1.75 m˜1.85 m;

(9) 3. Pressing: Pressing was conducted via a pressing machine, with a pressure of 4 Mpa;

(10) 4. Mold-locking: After the plate-mold assembly was pressed to specified thickness, mold-locking was conducted, then the mold-locking assembly moved out from the pressing machine and go to the operation of maintaining pressure;

(11) 5. Pressure-maintaining: Mold-locking state was kept for 24 h;

(12) 6. Plate-separating: After reaction was completed, mold-unlocking and plate-separating was conducted;

(13) 7. Leaving plate in a still condition: The plate was placed in a semi-finished product storehouse for 7 days;

(14) 8. Rough edge-sawing: Due to roughness, each side of plate material was cut off by 1 cm via a saw;

(15) 9. Drying: The temperature of drying tunnel was kept at 90˜100° C., and drying time was 1.5 h, and the moisture content of needle-inserting method was 13%˜15%.

(16) 10. Sanding: A 40-mesh sandpaper was used at the 1st sander holder, and a 80-mesh sandpaper was used at the 2nd sander holder, and a 120-mesh sandpaper was used at the 3rd sander holder, and a 180-mesh sandpaper was used at the 4th sander holder, and the required thickness of finished product is ±0.05 mm, and surface shall be smooth, and everywhere shall be rubbed by sandpaper;

(17) 11. Fine edge-sawing: The thickness at front-end and both sides of plate was smaller than normal range after sanding, and diagonal line difference is within ±3 mm.

(18) 10, 12. Packing: Each plate was checked to see whether there is breakage, unrubbed part, etc., and packing was conducted in accordance with requirements.

(19) As shown in FIG. 1˜FIG. 5, the plate material produced in this embodiment has good performance in many aspects.

(20) Specifically, density is 1.1 g/cm.sup.3. Moisture content is 10˜20 wt %. Expansion rate of water absorption of 24 h is 0. Internal bond strength is 0.77 MPa. Screw-holding force of board surface is 1140 N. Screw-holding force of board side is 1320 N. Breaking load is 760 N. In regard to bittern resistance, there is no water or damp. Thermal conductivity is 0.24 wW/(m.Math.k). Released formaldehyde is ‘not detected’. Calorific value is 1.1 MJ/kg. Mass loss rate of combustion is 39.8%.

EMBODIMENTS

Embodiment 1

(21) 1. Material-mixing: 2000 KG of xylem fiber, 100 kg of magnesium oxide, 50 kg of magnesium chloride, 23 kg of calcium chloride, 16 kg of silicon dioxide, 10 kg of magnesium sulfate, and 18 kg of hydrochloric acid were weighed out, and the additives were dispersed in water to form a liquid dispersion with a certain concentration, then the uniformly-dispersed liquid dispersion was used to wet xylem fiber, and after uniform wetting, the uniformly-mixed material went into a material-spreading silo;

(22) 2. Material-spreading: The material-spreading thickness of each plate was 5 cm, and pre-pressing thickness was 2 cm, and weight was 40 kg˜42 kg, and the number of spread plates was 60, and the plate pile-up height was 1.65 m˜1.75 m;

(23) 3. Pressing: Pressing was conducted via a pressing machine, with a pressure of 4 Mpa;

(24) 4. Mold-locking: After the plate-mold assembly was pressed to specified thickness, mold-locking was conducted, then the mold-locking assembly moved out from the pressing machine and go to the operation of maintaining pressure;

(25) 5. Pressure-maintaining: Mold-locking state was kept for 36 h;

(26) 6. Plate-separating: After reaction was completed, mold-unlocking and plate-separating was conducted;

(27) 7. Leaving plate in a still condition: The plate was placed in a semi-finished product storehouse for 7 days;

(28) 8. Rough edge-sawing: Due to roughness, each side of plate material was cut off by 1 cm via a saw, and diagonal line difference is within ±3 mm;

(29) 9. Packing: Each plate was checked to see whether there is breakage, and packing was conducted in accordance with requirements.

(30) In this embodiment, there is no need to conduct sanding treatment, so no need to conduct drying. The plate material of this embodiment has a certain degree of water-absorbing property and moisture-absorbing property, so the moisture content of plate material will be automatically adjusted by the plate material according to ambient environment. The plate material of this embodiment has a certain degree of water-absorbing property and moisture-absorbing property, but it will hardly expand after water absorption or dilution, and can still maintain a good size-stability and a good mechanical properties.

Embodiment 2

(31) 1. Material-mixing: 2500 KG of xylem fiber, 165 kg of magnesium oxide, 68 kg of magnesium chloride, 12 kg of boron oxide, 16 kg of aluminum sulfate, 10 kg of magnesium phosphate, 10 kg of citric acid, and 15 kg of sulfuric acid were weighed out, and the additives were dispersed in water to form a liquid dispersion with a certain concentration, then the uniformly-dispersed liquid dispersion was used to wet xylem fiber, and after uniform wetting, the uniformly-mixed material went into a material-spreading silo;

(32) 2. Material-spreading: The material-spreading thickness of each plate was 10 cm, and pre-pressing thickness was 5 cm, and weight was 80 kg˜82 kg, and the number of spread plates was 30, and the plate pile-up height was 1.65 m˜1.75 m;

(33) 3. Pressing: Pressing was conducted via a pressing machine, with a pressure of 6 Mpa;

(34) 4. Mold-locking: After the plate-mold assembly was pressed to specified thickness, mold-locking was conducted, then the mold-locking assembly moved out from the pressing machine and go to the operation of maintaining pressure;

(35) 5. Pressure-maintaining: Mold-locking state was kept for 24 hours;

(36) 6. Plate-separating: After reaction was completed, mold-unlocking and plate-separating was conducted;

(37) 7. Leaving plate in a still condition: The plate was placed in a semi-finished product storehouse for 7 days;

(38) 8. Rough edge-sawing: Due to roughness, each side of plate material was cut off by 1 cm via a saw;

(39) 9. Drying: The temperature of drying tunnel was kept at 90˜100° C., and drying time was 1.5 h, and the moisture content of needle-inserting method was 13%˜15%.

(40) 10. Sanding: A 40-mesh sandpaper was used at the 1st sander holder, and a 80-mesh sandpaper was used at the 2nd sander holder, and a 120-mesh sandpaper was used at the 3rd sander holder, and a 180-mesh sandpaper was used at the 4th sander holder, and the required thickness of finished product is ±0.05 mm, and surface shall be smooth, and everywhere shall be rubbed by sandpaper;

(41) 11. Fine edge-sawing: The thickness at front-end and both sides of plate was smaller than normal range after sanding, and diagonal line difference is within ±3 mm.

(42) 12. Packing: Each plate was checked to see whether there is breakage, unrubbed part, etc., and packing was conducted in accordance with requirements.

(43) Performance Test

(44) From FIG. 1, we can see that when frequency is 125 Hz, sound reduction index is 21.4 dB; when frequency is 250 Hz, sound reduction index is 41.7 dB; when frequency is 500 Hz, sound reduction index is 49.6 dB; when frequency is 1000 Hz, sound reduction index is 57.1 dB; when frequency is 2000 Hz, sound reduction index is 62.3 dB; when frequency is 4000 Hz, sound reduction index is 59.6 dB. The evaluation result according to GB/T 50121-2005 (ISO717-1) is: R.sub.w (C; C.sub.tr)=49 (−6; −12) dB.

(45) From FIG. 2, we can see that duration of combustion of this product is 0, and mass loss rate is 39.8%, and calorific value is 1.1 MJ/kg, and smoke toxicity AQ.sub.1=100, and experimental animals will not die within a poisoning period of 30 min and within three days after being poisoned, and will recover their average weight.

(46) From FIG. 3, we can see that the standard requirement of bacteria resistance rate is ≥90%, and this product is 100%; the standard requirement of mold resistance rating is class 0 or class 1, and this product is class 0; There is no requirement for the standard of freezing and thawing resistance, and the measured value of this product is ‘no cracking and stratification after 25 cycles of freezing and thawing’.

(47) From FIG. 4, we can see that the density of this product is 1.1 g/m.sup.3, moisture content is 17.8%, and thickness expansion rate of water absorption of 24 h is 0%, internal bond strength is 0.77 MPa, and screw-holding force of board surface is 1140 N, and breaking load is 760 N, and bittern resistance is ‘no water, no damp’, and thermal conductivity is 0.24 W/(m.Math.k), and internal exposure index is 0.0, and external exposure index is 0.0. From FIG. 5, we can see that released formaldehyde is ‘not detected’.

(48) From FIG. 6, we can see that screw-holding force of board side is 1320 N, test standard is GB/T 17657-2013.

(49) Thus it can be seen that a product of this invention may have some remarkable advantages compared with various plate materials of prior art.