A composite board with high fire resistance and flame retardant properties and its preparation method

Abstract

The invention relates to the technical field of flame retardant plywood production, and discloses a composite board with high fire retardant performance and a preparation method thereof, wherein the preparation method comprises: (1) dipping: laying a rock wool board on a grid plate pad, placing the board in a dipping cage, dipping the dipping cage in a dipping pool, floating the dipping cage up and down, and then draining; (2) applying glue: squeezing out excess diluted adhesive, spraying adhesive on the glue-extruded rock wool board, and then placing the board on a squeezing and squeezing platform again for secondary glue extrusion; (3) inserting holes: vertically punching multiple rows of holes on the rock wool board after secondary glue extrusion; (4) drying; (5) assembling: after the rock wool board obtained in step (4) is separated from the grid plate pad, the board is assembled with multiple wood veneers to form a substrate board; (6) forming: the substrate board is subjected to a hot pressing process to form a composite plywood, and the composite board prepared by the method of the invention has high flame retardant and fire retardant performance, high physical strength, and a wider range of applications.

Description

Technical Field

[0001] The invention relates to the technical field of flame retardant plywood production, in particular to a composite board with high fireproof and flame retardant performance and a preparation method thereof. Background Art

[0002] For a long time, my country and foreign countries have been committed to solving the fire prevention problem of wood decorative materials and have been committed to the development of fire-retardant and flame-retardant boards. At present, although the wood has met certain flame retardant requirements through the modification of adhesives and the addition of flame retardant materials, flame retardant boards and fireproof boards have been developed, they cannot solve the actual problem of fire prevention.

[0003] Rock wool is widely used in building thermal insulation, with low density, low strength, low price and easy manufacturing. Rock wool is an artificial inorganic fiber processed by high temperature melting, which has the characteristics of light weight, low thermal conductivity, heat absorption and non-combustibility.

[0004] However, due to the low strength and physical and mechanical properties of rock wool, and the dry rock wool board, it is difficult for the commonly used adhesive to penetrate into the rock wool board, thereby reducing the use strength of the plywood. Therefore, in the current conventional method of preparing flame-retardant plywood, rock wool cannot be used to produce artificial boards during the processing of artificial boards. Simply applying rock wool plywood to plywood has poor bonding effect, the product is prone to cracking, the strength of the plywood is reduced, and the flame retardant effect is limited, which affects the use scenarios of the plywood. Summary of the invention

[0005] Therefore, it is necessary to provide a composite board with high fire retardant performance and a preparation method thereof to solve the problem that the effect of applying rock wool to plywood in the prior art is not ideal.

[0006] To achieve the above object, the present invention provides a method for preparing a composite board with high fire retardant performance, comprising the following steps:

[0007] (1) Dipping: Lay the rock wool board flat on the grid plate, then put the grid plate into the dipping cage, immerse the dipping cage in the dipping pool, float the dipping cage up and down continuously, then drain, repeat the dipping N times, N ≥ 1; there is diluted adhesive in the dipping pool;

[0008] (2) Gluing: The grid plate with rock wool board is taken out of the cage and placed on the squeezing and squeezing platform to squeeze out the excess diluted adhesive in the rock wool board blank. The glued rock wool board is sprayed with adhesive containing 10% thickener. During the spraying, the glue is sprayed on both sides. After that, it is placed on the squeezing and squeezing platform again for secondary squeezing.

[0009] (3) Plug holes: vertically punch multiple rows of holes on the rock wool board after secondary glue extrusion;

[0010] (4) Drying: The rock wool board after jacking is dried at 40°C-65°C to control the moisture content of the rock wool board after impregnation to between 15% and 20%;

[0011] (5) Assembling: After the rock wool board and the grid plate obtained in step (4) are separated from the board, they are assembled with a plurality of wood veneers to form a substrate board;

[0012] (6) Forming: The base board is formed into a composite plywood through a hot pressing process.

[0013] Furthermore, the bottom surface of the grid plate pad is a mesh frame surface, a plurality of placement layers are arranged on the dipping cage, the placement layers are provided with grid holes, the grid plate pad is placed on the placement layers, the total dipping time of step (1) is 0.5-1 minute, when draining, the dipping cage is lifted out of the dipping pool, the dipping cage is first leaned at an angle of 45° on the inclined surface of the dipping table to drain the glue for 20-30 minutes, then the dipping cage is stood up to drain the glue, the draining time is 0-30 minutes, and then the dipping cage is stood up in a cone with one corner of the bottom as a fulcrum to drain the glue, the draining time is 20-30 minutes.

[0014] Furthermore, in step (2), when the rock wool board is sprayed with glue, the glue amount is 200-250g / square meter, and the thickener is flour. In step (3), the spacing between two adjacent rows of holes is 20-40cm, the spacing between holes in the same row is 10-20cm, and the diameter of the hole is 10-15mm.

[0015] Further, in step (5), the wood veneer is dried, flame-retardant and glue-coated before being assembled with the rock wool board. After the wood veneer is dried, the moisture content is controlled below 6%. The flame-retardant and glue-coating method of the wood veneer after drying is one of the following two methods:

[0016] (1) The wood veneer is immersed in a container containing flame retardants, insect repellents, and preservatives, and then dried in a dryer after flame retardant treatment, and then coated with adhesive;

[0017] (2) Add flame retardants, insect repellents, preservatives, and waterproofing agents to the adhesive. When the adhesive is phenolic adhesive, no waterproofing agent is added. After the adhesive is adjusted, it is rolled on the wood veneer. The amount of adhesive applied is 160-200 g / m 2 .

[0018] Furthermore, in step (5), the wood veneers located on the upper and lower surfaces of the substrate board do not need to be coated with glue, and the wood grains of two adjacent wood veneers are arranged crosswise in the top projection.

[0019] Furthermore, in the step (5), when the rock wool board is assembled, a reinforcement sheet is obliquely inserted on the rock wool board, and the reinforcement sheet is a thin sheet of the above-mentioned dried and flame-retardant wood veneer that is cut along the wood grain.

[0020] Further, in step (5), rock wool board, glass magnesium board, and multiple wood veneers are assembled and laid to form a substrate board.

[0021] A high fire retardant composite board prepared by the above-mentioned preparation method includes a plurality of stacked wood veneers and rock wool boards, wherein the rock wool board is located in the middle of the plurality of wood veneers, and the rock wool board is provided with a plurality of rows of holes, and the wood veneers and the rock wool boards and the wood veneers are bonded by adhesive.

[0022] Furthermore, two rows of tie bars are arranged between two adjacent rows of holes on the rock wool board, and the two rows of tie bars are symmetrically arranged to be inclined toward each other, with an inclination angle of 60-70°. The tie bars are flame-retardant treated and inserted into the rock wool board to further enhance the physical properties of the rock wool board.

[0023] Furthermore, a glass magnesium board is included, and the glass magnesium board is located between the rock wool board and the wood veneer. The composite glass magnesium board helps to improve the flame retardant effect of the composite board.

[0024] The above technical solution has the following beneficial effects:

[0025] In the present invention, the surface of the rock wool board is moistened by the gum dipping process of step (1), so that the mixed glue solution of the original gum and the flour additive etc. can be applied to the rock wool board later. After the short gum dipping process, the rock wool can be fully bonded with the wood veneer, and after the subsequent hot pressing and shaping, a plywood with good quality and not easy to crack can be obtained. At the same time, the drying time can also be reduced. The rock wool board after gum dipping and draining still contains excess diluted adhesive. The squeezing and squeezing platform can further squeeze out the excess diluted adhesive in the rock wool board blank. The multiple rows of holes on the rock wool board allow the rock wool to have a certain deformation space, which can improve the overall physical and mechanical properties of the rock wool board to a certain extent, so that the prepared plywood can have a strong physical strength while having the flame retardant effect of rock wool. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural diagram of the dipping cage and the grid plate pad described in the specific implementation method;

[0027] Figure 2 It is a structural diagram of the interior of the dipping cage and the grid plate pad described in the specific implementation method;

[0028] Figure 3 is a cross-sectional structural diagram of the composite plate described in Example 2-3;

[0029] Figure 4 This is a structural diagram of the rock wool board described in Example 2-3;

[0030] Figure 5 is a cross-sectional structural diagram of the composite plate described in Example 4;

[0031] Description of reference numerals:

[0032] 1. Glue dipping cage; 11. Placement layer; 12. Grid holes; 13. Auxiliary wheels; 2. Grid plate pad; 3. Safety door;

[0033] 4. Wood veneer; 5. Rock wool board; 51. Holes; 52. Tie rods; 6. Glass magnesium board. DETAILED DESCRIPTION

[0034] In order to explain the technical content, structural features, achieved objectives and effects of the technical solution in detail, the following is a detailed description in conjunction with specific embodiments and accompanying drawings.

[0035] Example 1

[0036] A method for preparing a composite board with high fire retardant performance comprises the following steps:

[0037] (1) Dipping:

[0038] (1.1) Figure 1-2 , lay the rock wool board flat on the grid plate pad 2, then put the grid plate pad 2 into the dipping cage 1, immerse the dipping cage 1 into the dipping pool, and the dipping cage 1 floats up and down continuously,

[0039] The bottom surface of the grid plate pad 2 is a mesh frame surface, and a multi-layer placement layer 11 is arranged on the dipping cage 1. The placement layer 11 is provided with grid holes 12, and the grid plate pad 2 is placed on the placement layer 11.

[0040] The mesh holes 12 and the mesh holes on the bottom of the grid plate pad 2 are arranged to facilitate the dipping of the bottom surface of the rock wool board, and the multi-layer placement layer 11 can simultaneously dip multiple rock wool boards.

[0041] In order to facilitate the cooperation between the grid plate pad 2 and the dipping cage 1, in this embodiment, the two opposite sides of the dipping cage 1 are respectively provided with an inlet and an outlet, and a safety door 3 is provided, and the placement layer 11 is provided with auxiliary wheels 13, and the bottom surface of the grid plate pad is provided with a long rolling track, and the rolling track cooperates with the auxiliary wheels 13. The cooperation between the rolling track and the auxiliary wheels 13 facilitates the grid plate pad 2 to enter and slide out of the dipping cage 1, and at the same time, it can also limit the shaking of the grid plate pad 2 back and forth during dipping.

[0042] In this embodiment, the size of the grid holes is 2.0-5.0 cm, the height of each layer is slightly larger than the thickness of the rock wool board (can reach 55-60 mm), the inner length and width of the bottom mesh frame of each layer is slightly larger than the rock wool board, and is slightly larger than the outer dimensions of the grid plate pad.

[0043] Taking the 4×8 foot finished board as an example, the size of the grid plate pad is about 2470×1250mm, and the adhesive used for dipping: the solid content of phenolic glue is 21-25%, and the solid content of modified urea-formaldehyde glue is 23-27%. Due to the large board surface and thick board, in order to evenly apply glue to the rock wool board, the dipping time is mainly determined by the thickness and density of the rock wool board. The total dipping time in this embodiment is 0.5-1 minute, and the total dipping time is short. After draining, repeat the dipping process once. The adhesive contains 1.5-3% mildew inhibitor. The modified urea-formaldehyde glue also contains 0.5-1% waterproofing agent (such as one or more mixtures of liquid paraffin, paraffin emulsifier, etc.)

[0044] (1.2) Drain and repeat dipping N times, N=1; the dipping pool contains diluted adhesive;

[0045] When draining, lift the glue cage out of the glue pool, lean it against the inclined glue draining platform at a 45° angle for 20-30 minutes, then stand it up to drain the glue, the draining time is 0-30 minutes, then use one corner of the bottom as a fulcrum, stand it up in a cone shape to drain the glue, the draining time is 20-30 minutes. The specific time is adjusted according to the specifications of the rock wool.

[0046] (2) Gluing: The grid plate with rock wool board is taken out of the cage and placed on the squeezing and squeezing platform to squeeze out the excess diluted adhesive in the rock wool board blank. The glued rock wool board is sprayed with adhesive containing 10% thickener. During the spraying, the glue is sprayed on both sides. After that, it is placed on the squeezing and squeezing platform again for secondary squeezing.

[0047] The squeezing and squeezing glue platform is provided with a working surface with an inclined angle of 5-10°. The squeezing and squeezing glue platform is an inclined surface, which is convenient for squeezing out and collecting the diluted glue.

[0048] In this embodiment, the glue squeezing plate is slowly pressed down to further squeeze out the excess diluted adhesive in the rock wool board blank without damaging the surface and internal integrity of the rock wool board. The rock wool fibers at the bottom are squeezed and compressed into the cavities of the grid plate pad. The rock wool board after squeezing and squeezing is tightly adsorbed on the grid plate pad. At this time, the thickness of the rock wool board is compressed from 30-50mm to about 5-10mm (after the pressure plate is lifted, the rock wool board rebounds)

[0049] When spraying glue on rock wool board, the glue application amount is 200-250g / square meter, and the thickener is flour.

[0050] (3) Holes: Multiple rows of holes are vertically punched on the rock wool board after secondary glue extrusion; the spacing between two adjacent rows of holes is 20-40 cm, the spacing between holes in the same row is 10-20 cm, and the diameter of the holes is 10-15 mm.

[0051] (4) Drying: The rock wool board after the jacking is dried at 40°C-65°C, so that the moisture content of the rock wool board after the dipped glue is controlled between 15-20%, and then it is ready for use;

[0052] (5) Assembling: After the rock wool board and the grid plate obtained in step (4) are separated from the board, they are assembled with a plurality of wood veneers to form a substrate board;

[0053] (5.1) Preparation of wood veneer: The wood veneer is dried, flame-retardant and glue-coated before being assembled with the rock wool board. After the wood veneer is dried, the moisture content is controlled below 6%. The flame-retardant and glue-coating methods of the wood veneer after drying are one of the following:

[0054] (S1) The wood veneer is immersed in a container containing flame retardant, insect repellent and preservative, and then dried in a dryer after flame retardant treatment, and then coated with adhesive;

[0055] (S2) Add flame retardant, insect repellent, preservative and waterproofing agent to the adhesive. When the adhesive is phenolic adhesive, no waterproofing agent is added. After adjusting the adhesive, apply it on the wood veneer with a roller. The amount of adhesive applied is 160-200g / m 2 .

[0056] In this embodiment, the original glue is provided with 10% thickener, such as flour, etc.

[0057] (5.2) Rock wool layer flipping and stripping: Flip the rock wool board and grid plate pad that have been punched and dried at low temperature after secondary rubber extrusion and pressing on the workbench of the assembly machine (or the side of the veneer assembly layer) by 180° (manual flipping or mechanical flipping machine flipping), and then use a rubber hammer or a wooden hammer to continuously knock on the back of the grid plate pad to demould the rubber-containing, low-temperature-dried, and well-punched rock wool board and separate it from the grid plate pad. The flipping and stripping process is used when the slab is assembled.

[0058] The wood veneers on the upper and lower surfaces of the substrate board do not need to be coated with glue, and the wood grains of the two adjacent wood veneers are cross-set in the top view projection.

[0059] When the rock wool board is assembled, a reinforcing bar is obliquely inserted on the rock wool board. The reinforcing bar is a thin sheet of the dried and flame-retardant wood veneer that is cut along the wood grain.

[0060] In step (5), the substrate board may include a rock wool board, a glass magnesium board, or a plurality of wood veneers.

[0061] (6) Forming: The base board is formed into a composite plywood through a hot pressing process.

[0062] The molding and hot pressing process is the same as that of existing traditional plywood.

[0063] (6.1) Aging: After the slabs are coated with glue and assembled, they are aged for 20-30 minutes.

[0064] (6.2) Prepressing: The slab is prepressed in a prepressing machine for 10-30 minutes with a unit pressure of 1.0-1.2 MPa.

[0065] (6.3) Hot pressing: After pre-pressing in the pre-pressing machine, the slab is sent to the hot press for hot pressing. The hot pressing temperature is 100-150℃, the hot pressing pressure is 0.6-1.0mpa, and the hot pressing time is 1.0-3.0min / mm for plywood.

[0066] (6.4) The hot pressed slabs are cured for 3-7 days. The cured slabs are sanded and sized, and then quality inspected, packaged and put into storage.

[0067] Example 2

[0068] like Figure 2-3 A high fire retardant composite board prepared according to the preparation method of Example 1 includes four stacked wood veneers 4 and a rock wool board 5, wherein the rock wool board 5 is located in the middle layer, and the rock wool board 5 has two rows of holes 51, the distance between the two rows of holes 51 is 40 cm, the spacing between the holes 51 in the same row is 20 cm, the diameter of the hole 51 is 15 mm, and two rows of tie bars 52 are arranged between the two rows of holes 51, and the two rows of tie bars 52 are symmetrically inclined toward each other, with an inclination angle of 60°.

[0069] Example 3

[0070] like Figure 2-3 A high fire retardant composite board prepared according to the preparation method of Example 1 includes four stacked wood veneers 4 and a rock wool board 5, wherein the rock wool board 5 is located in the middle layer, and the rock wool board 5 has two rows of holes 51, the distance between the two rows of holes 51 is 20 cm, the spacing between the holes 51 in the same row is 10 cm, the diameter of the hole 51 is 10 mm, and two rows of tie bars 52 are arranged between the two rows of holes 51, and the two rows of tie bars 52 are symmetrically inclined toward each other, with an inclination angle of 70°.

[0071] Example 4

[0072] A high fire retardant composite board prepared according to the preparation method of Example 1, comprising two wood veneers 4, a rock wool board 5, a glass magnesium board 6, and two wood veneers 4 stacked in sequence, the rock wool board 5 having two rows of holes 51, the distance between the two rows of holes 51 being 30 cm, the spacing between the holes 51 in the same row being 15 cm, the diameter of the hole 51 being 12.5 mm, and two rows of tie bars 52 being arranged between the two rows of holes 51, the two rows of tie bars 52 being symmetrically inclined toward each other, and the inclination angle being 65°.

[0073] Comparative Example 1

[0074] A high fire-retardant composite board comprises two wood veneers, a rock wool board and two wood veneers which are stacked in sequence. The rock wool board and the wood veneers are not subjected to the steps of dipping in glue and inserting holes before being assembled. After the steps of gluing and drying, the rock wool board is assembled with the wood veneers and then hot-pressed.

[0075] The composite boards of Examples 2-4 and Comparative Example 1 were tested for flame retardancy and physical properties. The test results are shown in Table 1.

[0076] Table 1 Performance test of composite board

[0077]

[0078] The bonding strength and elastic modulus of Control Example 1 are the maximum values ​​that can be achieved by the existing method. From the above table, it can be seen that the preparation method of the present invention not only makes the composite board have the flame retardant effect of rock wool, but also the rock wool board and the wood veneer are tightly bonded. The bonding strength between the rock wool board and the wood veneer can further break through the upper limit of the composite board of Control Example 1, and the value of the elastic modulus of the entire composite board has also been further broken through, which effectively improves the quality of the composite board. At the same time, the composite board has higher physical properties, which makes the application range of the composite board wider. Technical personnel in this field can also use this as a research direction to study composite boards with higher rock wool board bonding strength and higher elastic modulus.

[0079] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "include..." or "comprise..." do not exclude the existence of other elements in the process, method, article or terminal device including the elements. In addition, in this article, "greater than", "less than", "exceed" and the like are understood to exclude the number itself; "above", "below", "within" and the like are understood to include the number itself.

[0080] Although the above embodiments have been described, once those skilled in the art know the basic creative concepts, they can make additional changes and modifications to these embodiments. Therefore, the above description is only an embodiment of the present invention and does not limit the patent protection scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a composite board with high fire retardancy, characterized in that: The steps include: (1) Glue dipping: Lay the rock wool board flat on the grid plate, then put the grid plate into the glue dipping cage, immerse the glue dipping cage in the glue dipping pool, and float the glue dipping cage up and down continuously, then drain, repeat the glue dipping N times, N ≥ 1; there is diluted adhesive in the glue dipping pool; (2) Gluing: The grid plate with rock wool board is taken out of the cage and placed on the squeezing and squeezing platform to squeeze out the excess diluted adhesive in the rock wool board blank. The glued rock wool board is sprayed with adhesive containing 10% thickener. When spraying, the glue is sprayed on both sides. Then, it is placed on the squeezing and squeezing platform again for secondary squeezing. (3) Plug holes: vertically punch multiple rows of holes on the rock wool board after secondary glue extrusion; (4) Drying: The rock wool board after insertion is dried at 40℃-65℃, so that the moisture content of the rock wool board after impregnation is controlled between 15-20%; (5) Assembling: After the rock wool board obtained in step (4) is separated from the grid plate backing plate, it is assembled with multiple wood veneers to form a base material board; (6) Forming: The base board is formed into a composite plywood through a hot pressing process; The bottom surface of the grid plate pad is a mesh frame surface, and a multi-layer placement layer is arranged on the dipping cage, and the placement layer is provided with grid holes, and the grid plate pad is placed on the placement layer. The total dipping time of step (1) is 0.5-1 minute. When draining, the dipping cage is lifted from the dipping pool, and the dipping cage is first leaned against the inclined surface dipping table at an angle of 45° to drain the glue for 20-30 minutes, and then the dipping cage is stood up to drain the glue, and the dipping time is 0-30 minutes. After that, the dipping cage is stood up in a cone shape with one corner of the bottom as a fulcrum to drain the glue, and the dipping time is 20-30 minutes; In step (2), when the rock wool board is sprayed with glue, the amount of glue applied is 200-250 g / m2, and the thickener is flour. In step (3), the spacing between two adjacent rows of holes is 20-40 cm, the spacing between holes in the same row is 10-20 cm, and the diameter of the holes is 10-15 mm; In step (5), the wood veneer is dried, flame-retardant and glue-coated before being assembled with the rock wool board. After the wood veneer is dried, the moisture content is controlled below 6%. The flame-retardant and glue-coating method of the wood veneer after drying is one of the following two: (1) The wood veneer is soaked in a container containing flame retardants, insect repellents, and preservatives, and then dried in a dryer for flame retardant treatment, and then coated with adhesive; (2) Add flame retardants, insect repellents, preservatives, and waterproofing agents to the adhesive. When the adhesive is phenolic adhesive, no waterproofing agent is added. After the adhesive is adjusted, it is rolled on the wood veneer and the amount of adhesive applied is 160-200g / m 2 ; In step (5), the wood veneers located on the upper and lower surfaces of the substrate board do not need to be coated with glue, and the wood grains of two adjacent wood veneers are arranged crosswise in the top projection; When the rock wool board is assembled, a reinforcing bar is obliquely inserted on the rock wool board. The reinforcing bar is a thin slice of the wood veneer that has been dried and flame-retardantly treated and cut along the wood grain.

2. The method for preparing a composite board with high fire retardancy according to claim 1, characterized in that: In step (5), rock wool board, glass magnesium board and a plurality of wood veneers are assembled and laid to form a base material board.

3. A high fire retardant composite board prepared by the preparation method according to claim 1, characterized in that: It comprises a plurality of stacked wood veneers and rock wool boards, wherein the rock wool board is located among the plurality of wood veneers, the rock wool board is provided with a plurality of rows of holes, and the wood veneers and the rock wool board and the wood veneers are bonded by adhesive.

4. The high fire retardant composite board according to claim 3, characterized in that: Two rows of tie bars are arranged between two adjacent rows of holes on the rock wool board, and the two rows of tie bars are symmetrically arranged and tilted toward each other, with an inclination angle of 60-70°.

5. The high fire retardant composite board according to claim 3, characterized in that: Also included is a glass magnesium board, which is located between the rock wool board and the wood veneer.

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