CN110843055A

CN110843055A - Fireproof multi-layer eucalyptus board and production method thereof

Info

Publication number: CN110843055A
Application number: CN201911208467.4A
Authority: CN
Inventors: 陈姗姗
Original assignee: Guangxi Hengxian Zhenglin Wood Co Ltd
Current assignee: Guangxi Hengxian Zhenglin Wood Co Ltd
Priority date: 2019-11-30
Filing date: 2019-11-30
Publication date: 2020-02-28

Abstract

The invention provides a fireproof multi-layer eucalyptus board and a production method thereof, wherein the production method of the multi-layer eucalyptus board comprises the steps of single board and thin board sorting, thin board gluing, cold pressing, hot pressing, standing and health preserving, dust scraping, sanding, repairing, edge cutting and panel pasting, and is characterized in that: the protection prevents glue and dries at hot pressing process is too fast around the slab before first hot pressing and last hot pressing with upper and lower surface spraying one deck fire prevention solidified membrane, and keep the inside stress of multiply wood, can also make urea-formaldehyde glue fully react completely, the multiply wood after making it the shaping is difficult for the fracture, the user use has reduced volatile formaldehyde, panel after the hot pressing is through the health preserving that stews, sand light and veneer, can saw limit packing and obtain fire prevention multilayer eucalyptus board product.

Description

Fireproof multi-layer eucalyptus board and production method thereof

Technical Field

The invention relates to a multi-layer wood board and a production method thereof, in particular to a fireproof multi-layer eucalyptus wood board and a production method thereof.

Background

The multi-layer wood board is a multi-layer board material formed by rotationally cutting wood sections into single boards or slicing wood squares into thin wood and gluing the single boards by using an adhesive, the fiber directions of the single boards of adjacent layers are usually mutually vertical to be glued, and the outer surfaces of the single boards are faced or not faced according to requirements, and the multi-layer wood board is also called a glued multi-layer board.

The multi-layer wood board is one of common materials for furniture, is one of three large boards of artificial boards, and can also be used as a material for airplanes, ships, trains, automobiles, buildings, packing boxes and the like. Typically with the skin and inner sheets symmetrically disposed on either side of the center layer or core. The glued veneer is pressed into the wood grain board blank by the criss-cross matching of the glued veneer according to the wood grain direction under the condition of heating or not heating. The number of layers is generally odd, and a few are even. The difference of physical and mechanical properties in the longitudinal and transverse directions is small. The common plywood types include three-ply board and five-ply board, and at present, the plywood types have more than seven layers. The plywood can improve the utilization rate of the wood and is a main way for saving the wood. The main tree species are: beech, cinnamomum camphora, willow, poplar, eucalyptus, and the like.

In order to improve the anisotropic properties of natural wood as much as possible, and to make the plywood uniform in properties and stable in shape, the general plywood structure should obey two basic principles: firstly, the symmetry is realized; and secondly, the fibers of the veneers of the adjacent layers are mutually vertical. The symmetry principle is that the veneers on both sides of the center plane of symmetry of the plywood are required to be symmetrical to each other no matter the wood properties, the thickness of the veneers, the number of layers, the fiber direction, the water content and the like. In the same veneer board, the veneer with single tree species and thickness can be used, and the veneer with different tree species and thickness can also be used; but any two layers of the single-board trees which are symmetrical to each other on the two sides of the symmetrical central plane have the same species and thickness. The front and back panels are allowed to be of different tree species.

In order to develop plywood production by fully and reasonably utilizing forest resources and achieve the purpose of using the plywood as much as possible, the newly established national standard in China is divided into plywood for coating (used for products such as furniture, sewing machine tables and various electrical appliance shells with surfaces needing to be coated with transparent coatings), plywood for decoration (used as a decoration material for buildings, furniture, vehicles, ships and floors), general plywood (suitable for packaging, underlayment and other purposes) and veneer decoration plywood (used as a high-grade decoration material for buildings, furniture, vehicles, ships and the like) according to the use condition of a veneer.

In recent years, the fast-growing eucalyptus tree species cultivated in eastern forest lands of Guangxi China is introduced in the provinces of Shuangguan, Yunnan, Fujian, Guizhou, Hainan and the like in the south of China, the fast-growing eucalyptus is a light-colored broad-leaved wood, the wood grain is compact and irregular, the sapwood layer is wide, and the fast-growing eucalyptus tree species is white to light pink; the heart material has a light brownish red color. At present, the fast-growing eucalyptus globulus grows fast, can be grown within 3 years, farmers in mountainous areas plant a large amount of the fast-growing eucalyptus globulus, which accounts for more than 50 percent of available wood in south, and in addition, the original tree species such as pine trees, fir trees, chinaberry trees and the like grow slowly, so that the fast-growing eucalyptus globulus can not be cut down randomly as a natural forest, the wood yield of 1 mu of fast-growing eucalyptus globulus is equivalent to the natural forest yield of more than 5 mu,

the eucalyptus only accounts for 13.7% of the forest area in Guangxi, but the wood requirements of more than 80% in Guangxi and more than 20% in China are met. At present, high-performance eucalyptus reconstituted wood, eucalyptus veneer laminated wood, bamboo eucalyptus composite material, thick-core eucalyptus solid wood composite board, formaldehyde-free eucalyptus plywood manufacturing technology and the like are successfully developed in China, and the application of eucalyptus in artificial boards is increasingly popularized.

The core layer of the solid wood composite multilayer board is formed by pressing eucalyptus single sheets through adhesives. Eucalyptus is a plant of MyrtaceaeMyrtaceaeEucalyptus genusEucalyptusThe eucalyptus is strong in adaptability, can grow in poor soil, is high in growth speed and low in nursing cost, and therefore the planting area is increased year by year. Eucalyptus wood is red, glossy, has no special smell, has staggered grains, dense structure, hard and heavy material and is easy to bend. The eucalyptus with larger diameter grade is rotary cut into a veneer to be used as a core board for producing plywood or laminated veneer lumber, and the eucalyptus with small diameter grade, branch wood or difficult rotary cut is processed into wood chips for papermaking or producing fiberboards, so that the comprehensive utilization rate of the eucalyptus can be improved to more than 90%.

At present, the solid wood composite floor is generally used for manufacturing furniture, wood floors and decorative plates, a plurality of factories are also used as production workshops and warehouse clapboards, in some warehouses for accommodating inflammable and explosive products, the ordinary wood boards are very dangerous to use as the clapboards, once the inflammable and explosive products are burnt or exploded, the clapboards become combustion-supporting materials, even if fire-fighting measures are provided, the fire behavior is difficult to control, and therefore people begin to use the combustion-supporting boards as the clapboards of the production workshops and the warehouses at present.

The applicant is a production enterprise adopting solid wood composite multilayer boards at present in the positive forest wood industry limited company in the horizontal county of Guangxi, and according to the market demands at home and abroad, the process characteristics of the existing eucalyptus composite boards are greatly improved, so that the eucalyptus composite boards which are less in volatile formaldehyde, high in strength and suitable for decoration materials of buildings, furniture, vehicles and ships are produced, and a plurality of Chinese patents are also applied, for example:

[1] a method for producing a full eucalyptus plywood by adopting insect-proof and mildew-proof composite urea resin, 201610746220.8, 106182218B, applicant: guangxi, prefecture, positive forest, wood industries, ltd, filing date: 2016-08-29, abstract: the method for producing the full eucalyptus plywood by adopting the insect-proof and mildew-proof composite urea-formaldehyde resin comprises the following steps: plank rotary sheet → veneer drying → gluing → three times of cold pressing → static curing → three times of hot pressing → heat dissipation curing → plate blank thickness fixing and sanding. The key of the production method is that melamine modified urea resin is adopted as a main material of the adhesive, and oxidized starch is added as a viscous complexing agent;

[2] a method for producing a eucalyptus and birch composite floor by adopting high-temperature resistant composite urea resin, 201610747076.X, 106272849B, applicant: guangxi, prefecture, positive forest, wood industries, ltd, filing date: 2016-08-29, abstract, the invention relates to a method for producing eucalyptus and birch composite floor by adopting high temperature resistant composite urea resin, which comprises the following steps: the method comprises the steps of wood plate turning → veneer drying → gluing → three times of cold pressing → standing and curing → three times of hot pressing → heat dissipation and curing → plate blank thickness-fixing and sanding → base material surface gluing → curing and grooving → paint spraying, drying and shaping. The key point of the production method is that melamine modified urea resin is adopted as the main material of the adhesive.

[3] Method for producing full eucalyptus plywood by adopting anticorrosive composite urea-formaldehyde resin, 201610747071.7, 106313201B, applicant: guangxi, prefecture, positive forest, wood industries, ltd, filing date: 2016-08-29, abstract: the method for producing the full eucalyptus plywood by adopting the anticorrosive composite urea resin comprises the following steps: plank rotary sheet → veneer drying → gluing → three times of cold pressing → static curing → three times of hot pressing → heat dissipation curing → plate blank thickness fixing and sanding. The key of the production method is that melamine modified urea resin is adopted as a main material of the adhesive, and oxidized starch is added as a viscous complexing agent;

[4] a method for producing a eucalyptus and birch composite floor by adopting insect-proof and mildew-proof composite urea resin, 201610747086.3, 106335120B, applicant: guangxi, prefecture, positive forest, wood industries, ltd, filing date: 2016-08-29, abstract, a method for producing eucalyptus and birch composite floor by adopting insect-proof and mildew-proof composite urea resin, which comprises the following steps: the method comprises the steps of wood plate turning → veneer drying → gluing → three times of cold pressing → standing and curing → three times of hot pressing → heat dissipation and curing → plate blank thickness-fixing and sanding → base material surface gluing → curing and grooving → paint spraying, drying and shaping. The key point of the production method is that melamine modified urea resin is adopted as the main material of the adhesive.

[5] A method for producing eucalyptus and birch composite floor by adopting weather-resistant composite urea resin, 201610746169.0, 106272848B, applicant: guangxi, prefecture, positive forest, wood industries, ltd, filing date: 2016-08-29, abstract, the invention relates to a method for producing eucalyptus and birch composite floor by adopting weather-resistant composite urea resin, which comprises the following steps: the method comprises the steps of wood plate turning → veneer drying → gluing → three times of cold pressing → standing and curing → three times of hot pressing → heat dissipation and curing → plate blank thickness-fixing and sanding → base material surface gluing → curing and grooving → paint spraying, drying and shaping. The key point of the production method is that melamine modified urea resin is adopted as the main material of the adhesive.

[6] Method for producing a cabinet panel using a flame retardant composite urea formaldehyde resin, 201610752586.6, applicant: guangxi, prefecture, positive forest, wood industries, ltd, filing date: 2016-08-29, abstract the invention relates to a household building material, in particular to a method for producing a cabinet plate by adopting flame-retardant composite urea-formaldehyde resin, wherein the structure of the cabinet plate from top to bottom is as follows: decorative paper, China fir veneers, shaving boards and back boards; the periphery of the cabinet plate is edged by aluminum alloy; and a flame-retardant composite urea-formaldehyde resin adhesive is coated between the fir veneer and the particle board, and a flame-retardant composite urea-formaldehyde resin is coated between the particle board and the back board.

In the process of producing and applying products, the applicant thinks of a plurality of technical schemes in the composite urea-formaldehyde resin adhesive, such as adding insect-proof and mildew-proof agents, flame retardants, preservatives, high-temperature resistant agents and the like, and overcomes the defect that a plurality of existing urea-formaldehyde resin adhesives release more formaldehyde, but the composite urea-formaldehyde resin adhesive has defects in some aspects, such as easy deformation of the products when pressure is not uniformly applied in the hot pressing process sometimes, non-uniform drying process sometimes, cracking phenomenon, non-uniform gluing sometimes, and over-standard formaldehyde of the products can not be ensured, and a plurality of technical indexes are still needed to be improved.

Disclosure of Invention

The technical scheme of the invention is as follows:

the invention provides a production method of a fireproof multi-layer eucalyptus board, which comprises the steps of single board and thin board sorting, thin board gluing, cold pressing, hot pressing, standing and health preserving, dust scraping, sanding, repairing, trimming and panel pasting, and is characterized in that: before the first hot pressing and the last hot pressing, a layer of curing film is sprayed on the periphery, the upper surface and the lower surface of the plate blank, the glue is prevented from being dried too fast in the hot pressing process, the stress in the multilayer plate is kept, the urea formaldehyde glue can be fully reacted completely, the formed multilayer plate is not easy to burn and crack, the volatile formaldehyde is reduced in the using process, and after the hot pressing, the plate can be subjected to standing, curing, sanding and panel pasting, and edge sawing and packaging to obtain a fireproof multilayer eucalyptus plate product;

the curing film is composed of thermosetting resin, a flame retardant, a curing agent and an auxiliary agent, wherein the thermosetting resin is melamine formaldehyde resin, furfuryl alcohol resin or acrylic resin, and the flame retardant comprises an inorganic flame retardant and an organic flame retardant; the curing agent is biuret, and the auxiliary agent comprises glass fiber, organic silicon, titanium dioxide and calcium carbonate; wherein the weight portion of the thermosetting resin is 40-60; 3-5 of a flame retardant; 3-8 parts of a curing agent; the balance of auxiliary agents or fillers.

The construction mode of the cured film is that the thermosetting resin, the curing agent and the auxiliary agent are made into powder, and the powder is sprayed on the periphery and the upper and lower surface of the plate blank after being mixed.

The cold pressing and the hot pressing are carried out for 2 times or 3 times, the cold pressing temperature is room temperature, the pressure is 0.8-1.0 MPa, and the hot pressing pressure is 1.5-2.0 MPa; the temperature of the first hot pressing is 120-125 ℃; the temperature of the second hot pressing is 115-120 ℃, and the temperature of the third hot pressing is 125-130 ℃; the standing and curing temperature is 80-90 ℃, and the time is 4-6 h.

The adhesive for gluing the thin plate is urea-formaldehyde resin or phenolic resin.

The veneer is prepared by sticking paint-free boards or boards with flatness and smoothness on the upper surface or upper and lower surfaces of a plurality of layers of eucalyptus boards, including poplar boards, fir boards and beech boards.

The inorganic flame retardant comprises aluminum hydroxide, antimony trioxide, magnesium hydroxide and microencapsulated red phosphorus; the organic flame retardant is tributyl phosphate, tri (2-carbonyl ethyl) phosphate, phosphite ester LM-K1500 and melamine.

The fireproof curing film consists of thermosetting resin, combustion improver, curing agent and auxiliary agent, wherein the thermosetting resin adopts melamine formaldehyde resin, furfuryl alcohol resin or acrylic resin, the curing agent for preventing the fire is biuret, and the auxiliary agent or filling agent comprises glass fiber, organic silicon, titanium dioxide and calcium carbonate. Wherein the weight portion of the thermosetting resin is 40-60; 3-8 parts of a curing agent; 3-5 parts of a combustion improver; the balance of auxiliary agents or fillers.

In the thermosetting resin described above: the physicochemical properties of various thermosetting resins are as follows:

melamine-formaldehyde resin (english name melamine-formaldehyde resin), a polymer obtained by reacting melamine with formaldehyde. The cross-linking reaction occurs during the processing and molding, and the product is infusible thermosetting resin. The cured melamine formaldehyde resin is colorless and transparent, is stable in boiling water, can be used even at 150 ℃, and has self-extinguishing property, arc resistance and good mechanical property.

Furfuryl alcohol resin, the english name furfurfurfuryl alcohol resin defines furan resin produced using furfuryl alcohol as a raw material. The curing agent is added at room temperature to be cured into the thermosetting material.

Acrylic resin, which is a generic name for polymers of acrylic acid, methacrylic acid and derivatives thereof. The acrylic resin coating is a thermoplastic or thermosetting resin coating prepared by using (methyl) acrylate and styrene as main components and acrylic resin obtained by copolymerizing the (methyl) acrylate and styrene with other acrylate, or an acrylic radiation coating.

The thermosetting acrylic resin is a resin which has a certain functional group in the structure and forms a network structure by reacting with the functional group in the added amino resin, epoxy resin, polyurethane and the like during paint preparation, and the thermosetting resin is generally relatively low in molecular weight. The thermosetting acrylic paint has excellent fullness, luster, hardness, solvent resistance and weather resistance, and does not change color or turn yellow when being baked at high temperature.

Curing agent biuret, which is white long-sheet crystal. Has no odor. It has hygroscopic property. The crystal in water contains 4 molecules of crystal water. At about 110 ℃ water is lost, at 193 ℃ it decomposes and at a higher temperature melamine is formed. Is easily soluble in ethanol and slightly soluble in diethyl ether.

Biuret, as an aliphatic polyurethane curing agent, has good weather resistance, good compatibility with solvents such as polyol or butyl acetate, and good high-temperature solvent resistance after curing with polyol-containing polymers.

The organosilicon product is of a main chain structure with silicon-oxygen (Si-O) bonds, the bond energy of C-C bonds is 82.6 kilocalories per gram molecule, and the bond energy of Si-O bonds is 121 kilocalories per gram molecule in the organosilicon, so that the organosilicon product has high thermal stability, and chemical bonds of molecules are not broken or decomposed at high temperature (or radiation irradiation). The organosilicon can resist high temperature and low temperature, and can be used in a wide temperature range. The change with temperature is small whether the chemical property or the physical and mechanical property is changed. The invention can select silane coupling agent, silicon oil (silicone grease, silicon emulsion, silicon surfactant), silicon resin and the like; the organic silicon has unique structure, combines the performances of inorganic materials and organic materials, has the basic properties of low surface tension, small viscosity-temperature coefficient, high compressibility, high gas permeability and the like, and has the excellent characteristics of high and low temperature resistance, electrical insulation, oxidation resistance stability, weather resistance, flame retardancy, hydrophobicity, corrosion resistance, no toxicity, no odor, physiological inertia and the like.

The flame retardant is prepared from the following materials: aluminum hydroxide, antimony trioxide, magnesium hydroxide and microencapsulated red phosphorus; the organic flame retardant is tributyl phosphate, tri (2-carbonyl ethyl) phosphate, phosphite ester LM-K1500, melamine and the like, and has the following functions: 1. endothermic, any combustion gives off limited heat over a relatively short period of time, and if a portion of the heat given off by the source is absorbed over a relatively short period of time, the flame temperature will drop, the amount of heat radiated to the combustion surface and acting to crack the vaporized combustible molecules into free radicals will be reduced, and the combustion reaction will be inhibited to some extent. Under the condition of high temperature, the fire retardant has strong endothermic reaction, absorbs part of heat released by combustion, reduces the temperature of the surface of combustible, effectively inhibits the generation of combustible gas and prevents the spread of combustion. The flame retardant mechanism of the Al (OH)3 flame retardant is to improve the flame retardant property of the polymer by increasing the heat capacity of the polymer to ensure that the polymer absorbs more heat before reaching the thermal decomposition temperature. The flame retardant fully exerts the characteristic of absorbing a large amount of heat when the flame retardant is combined with water vapor, and improves the flame retardant capability of the flame retardant. 2. The flame retardant can form a glass or stable foam covering layer at high temperature after being added into the multilayer board, so that oxygen is isolated, and the flame retardant has the functions of insulating heat, isolating oxygen and preventing combustible gas from escaping outwards, thereby achieving the purpose of flame retardance. For example, the organic phosphorus flame retardant can generate a cross-linked solid substance or a carbonized layer with a more stable structure when heated. The formation of the carbonized layer can prevent the polymer from further pyrolysis on the one hand and prevent the thermal decomposition products in the carbonized layer from entering the gas phase to participate in the combustion process on the other hand. 3. Chain reactions are suppressed and, according to the chain reaction theory of combustion, it is the radicals that are required to sustain combustion. The flame retardant can act on the gas-phase combustion area to capture free radicals in the combustion reaction, so that the propagation of flame is prevented, the flame density in the combustion area is reduced, and finally the combustion reaction speed is reduced until the combustion reaction is stopped. Some flame retardants, which have an evaporation temperature that is the same as or similar to the decomposition temperature of the polymer, also volatilize when the polymer is decomposed by heat. At the moment, the flame retardant and the thermal decomposition products are simultaneously positioned in a gas phase combustion area, so that free radicals in the combustion reaction can be captured, and the combustion chain reaction is interfered. 4. The non-combustible gas has a suffocation function, the non-combustible gas is decomposed when the flame retardant is heated, and the concentration of the combustible gas decomposed from the combustible substances is diluted to be lower than the lower limit of combustion. Meanwhile, the flame retardant has the function of diluting the oxygen concentration in the combustion zone, prevents the combustion from continuing, and achieves the flame retardant function.

The invention has the following prominent substantive characteristics and remarkable progress:

1. with the improvement of the living standard of people, the requirements for home decoration are also continuously improved. The multilayer board becomes the preferred material for home furniture or floor decoration because of natural and elegant grains and good texture. The multilayer composite board overcomes the defects of wet expansion and dry shrinkage of the solid wood board, has better dimensional stability, and simultaneously keeps the natural wood grain and comfortable foot feel of the solid wood floor, thereby becoming an important variety in the floor. The solid wood composite board can be formed by alternately laminating boards of different tree species, overcomes the defect of unidirectional isotropy of the solid wood board, and has small dry shrinkage and wet expansion rate. The solid wood composite board has the advantages of both the stability of the reinforced board and the attractiveness of the solid board, and is environment-friendly, and the solid wood composite board has the advantages of a common solid board, effectively adjusts the internal stress between woods, and overcomes the defect that the deformation of the woods is large along with the change of seasonal humidity, so that the solid wood composite board is popular with consumers.

2. In the prior art, if the product is easy to deform when pressure is not uniform enough sometimes in the hot pressing process of the multilayer board, sometimes the drying process is not uniform enough, cracking occurs, some glue applying is not uniform, and the formaldehyde of the product cannot exceed the standard, a layer of curing film is sprayed on the periphery and the upper part and the lower part of the surface of the board blank before the first hot pressing and the last hot pressing, so that the glue is prevented from being dried too fast in the hot pressing process, the stress in the multilayer board is kept, the urea formaldehyde glue can be fully reacted, the formed multilayer board is not easy to crack, and the volatile formaldehyde is reduced in the using process of a user.

3. The invention relates to a spraying fireproof curing film on a eucalyptus plate, which consists of thermosetting resin, a combustion improver, a curing agent and an auxiliary agent. The flame retardant is an application of a flame retardant technology in actual life, is a special chemical auxiliary agent for improving the combustion performance of combustible and combustible materials, and is widely applied to flame retardant processing of various decoration materials. The material processed by the flame retardant can effectively prevent, delay or stop the propagation of flame, thereby achieving the flame retardant effect. The flame retardant added in the invention comprises aluminum hydroxide, antimony trioxide, magnesium hydroxide and microencapsulated red phosphorus; the organic flame retardant is tributyl phosphate, tris (2-carbonyl ethyl) phosphate, phosphite ester LM-K1500, melamine and the like, has good compatibility with wood board fibers, does not change the inherent excellent performance of the original substances, and has small dosage and large effect; does not decompose at the processing temperature; the wood board has low toxicity, does not generate toxic gas during combustion, and is suitable for being used as a wood board in home decoration or movie theaters and public places.

4. The fireproof multilayer solid wood composite board can be applied to manufacturing bedrooms, living rooms, study rooms and offices, can also be used as a wood floor, has long service life and needs long-time environmental destruction inspection. The urea formaldehyde and phenol formaldehyde glue applied to the solid wood composite board adhesive in the market at present release formaldehyde greatly, and before the first hot pressing and the last hot pressing, a layer of fireproof curing film is sprayed on the periphery and the upper part and the lower part of the surface of the plate blank, so that the strength is improved, the formaldehyde release concentration is greatly reduced, and the fireproof effect is good.

Drawings

FIG. 1 is a process flow diagram of the production method of the fireproof multi-layer eucalyptus board.

The production method of the fireproof multilayer board comprises the steps of single board sheet sorting, sheet gluing, three times of cold pressing, three times of hot pressing, two times of standing and health preserving, dust scraping, sanding, repairing, edge cutting and panel pasting, and is characterized in that: at first cold pressing, repair the side cut, around the slab surface with the upper and lower spraying one deck fire prevention solidified film before first hot pressing and the hot pressing of third time, the protection prevents glue at hot pressing in-process drying excessively, and keep the inside stress of multiply wood, urea-formaldehyde glue fully reacted completely can also make it, the multiply wood fire prevention after making it the shaping, be difficult for the fracture, the user use has reduced volatile formaldehyde, panel after the hot pressing of third time is through the health preserving of stewing, sand light and veneer, can saw the limit packing obtain fire prevention multilayer eucalyptus board product.

Detailed Description

Example 1

The production method of the fireproof multi-layer eucalyptus board comprises the steps of single board sheet sorting, sheet gluing, three-time cold pressing, three-time hot pressing, two-time standing and health preserving, dust scraping, sanding, repairing, trimming and panel pasting, and is characterized in that: at first cold pressing, repair the side cut, around the slab surface with the upper and lower spraying one deck fire prevention solidified film before first hot pressing and last hot pressing, the protection prevents glue at hot pressing in-process drying excessively fast, and keep the inside stress of multiply wood, urea-formaldehyde glue fully reacts completely can also make it, the multiply wood after the shaping that makes it is difficult for burning and the fracture, the user use has reduced volatile formaldehyde, the panel is through the health preserving of stewing after the hot pressing of third time, sand light and veneer, can saw the limit packing obtain fire prevention multilayer eucalyptus board product.

The construction mode of the cured film is that the thermosetting resin, the curing agent and the auxiliary agent are made into powder and sprayed on the periphery, the upper surface and the lower surface of the plate blank after being mixed. And firmly attaching the curing film to the outer surface of the plate blank through the high temperature of the hot pressing process.

The cold pressing temperature is room temperature, the pressure is 0.8-1.0 MPa, and the hot pressing pressure is 1.5-2.0 MPa; the temperature of the first hot pressing is 120-125 ℃; the temperature of the second hot pressing is 115-120 ℃, and the temperature of the third hot pressing is 125-130 ℃; the standing and curing temperature is 80-90 ℃, and the time is 4-6 h.

The adhesive for gluing the thin plate is urea-formaldehyde resin.

The fireproof curing film is composed of thermosetting resin, a flame retardant, a curing agent and an auxiliary agent, wherein the thermosetting resin is melamine formaldehyde resin, the curing agent is biuret, the flame retardant is a mixture of melamine and antimony trioxide in a ratio of 1:1, and the auxiliary agent or the filler comprises glass fiber, organic silicon, titanium dioxide and calcium carbonate. Wherein the weight portion of the thermosetting resin is 40-50; flame retardant 3, curing agent 5; auxiliary agent and filler glass fiber, organic silicon, titanium dioxide and calcium carbonate, wherein the balance is 10-13 parts of glass fiber; 5 parts of organic silicon, 9 parts of titanium dioxide and the balance of calcium carbonate.

Example 2

The production method of the fireproof multi-layer eucalyptus board comprises the steps of single board sheet sorting, sheet gluing, primary cold pressing, secondary hot pressing, secondary standing and health preserving, dust scraping, sanding, repairing, trimming and panel pasting, and is characterized in that: at first cold pressing, repair the side cut, around the slab surface with spray one deck solidified film from top to bottom before first hot pressing and the second hot pressing, the protection prevents glue at hot pressing process drying excessively fast, and keep the inside stress of multiply wood, urea-formaldehyde glue fully reacted completely can also make, the multiply wood after the shaping that makes is difficult for burning and the fracture, the user use has reduced volatile formaldehyde, panel after the third hot pressing is through the health preserving that stews, sand light and veneer pasting, can saw the limit packing obtain fire prevention multilayer eucalyptus board product.

The construction method of the curing film is that the thermosetting resin, the curing agent and the auxiliary agent are made into powder, the powder is sprayed on the periphery, the upper surface and the lower surface of the plate blank after being mixed, and the curing film is firmly attached to the outer surface of the plate blank through the high temperature in the hot pressing process.

The cold pressing temperature is room temperature, the pressure is 0.8-1.0 MPa, and the hot pressing pressure is 1.5-2.0 MPa; the temperature of the first hot pressing is 120-125 ℃; the temperature of the second hot pressing is 120-130 ℃; the standing and curing temperature is 80-90 ℃, and the time is 4-6 h.

The adhesive for gluing the thin plate is modified phenolic resin.

The curing film is composed of thermosetting resin, a curing agent and an auxiliary agent, wherein the thermosetting resin is acrylic resin, the curing agent is biuret, and the flame retardant is a mixture of phosphite ester LM-K1500 and aluminum hydroxide in a mass ratio of 1: 1; the auxiliary agent or the filler comprises glass fiber, organic silicon, titanium dioxide and calcium carbonate. Wherein the weight portion of the acrylic resin is 50-60; a flame retardant 5; a curing agent 5; auxiliary agent and filler glass fiber, organic silicon, titanium dioxide and calcium carbonate, wherein the balance is 12-15 parts of glass fiber; 8 percent of organic silicon, 5 percent of titanium dioxide and 100 percent of calcium carbonate.

The characteristics of the product with the fireproof curing film are compared with those of the product without the fireproof curing layer:

Claims

1. the production method of the fireproof multi-layer eucalyptus board comprises the steps of single board sheet separation, sheet gluing, cold pressing, hot pressing, standing, health preserving, dust scraping, sanding, repairing, trimming and veneer pasting, and is characterized in that: before the first hot pressing and the last hot pressing, a layer of curing film is sprayed on the periphery, the upper surface and the lower surface of the plate blank, the glue is prevented from being dried too fast in the hot pressing process, the stress in the multilayer plate is kept, the urea formaldehyde glue can be fully reacted completely, the formed multilayer plate is not easy to burn and crack, the volatile formaldehyde is reduced in the using process, and after the hot pressing, the plate can be subjected to standing, curing, sanding and panel pasting, and edge sawing and packaging to obtain a fireproof multilayer eucalyptus plate product;

the curing film is composed of thermosetting resin, a flame retardant, a curing agent and an auxiliary agent, wherein the thermosetting resin is melamine formaldehyde resin, furfuryl alcohol resin or acrylic resin, and the flame retardant comprises an inorganic flame retardant and an organic flame retardant; the curing agent is biuret, and the auxiliary agent comprises glass fiber, organic silicon, titanium dioxide and calcium carbonate; wherein the weight portion of the thermosetting resin is 40-60; 3-5 parts of flame retardant and 3-8 parts of curing agent; the balance of auxiliary agents or fillers.

2. The method for producing a fire-retardant multi-layer eucalyptus board as claimed in claim 1, wherein: the construction mode of the cured film is that the thermosetting resin, the curing agent and the auxiliary agent are made into powder, and the powder is sprayed on the periphery and the upper and lower surface of the plate blank after being mixed.

3. The method for producing a fire-retardant multi-layer eucalyptus board as claimed in claim 1, wherein: the cold pressing and the hot pressing are carried out for 2 times or 3 times, the cold pressing temperature is room temperature, the pressure is 0.8-1.0 MPa, and the hot pressing pressure is 1.5-2.0 MPa; the temperature of the first hot pressing is 120-125 ℃; the temperature of the second hot pressing is 115-120 ℃, and the temperature of the third hot pressing is 125-130 ℃; the standing and curing temperature is 80-90 ℃, and the time is 4-6 h.

4. The method for producing a fire-retardant multi-layer eucalyptus board as claimed in claim 1, wherein: the adhesive for gluing the thin plate is urea-formaldehyde resin or phenolic resin.

5. The method for producing fireproof multi-layer eucalyptus board according to claim 1, wherein the veneer is made by sticking paint-free boards or boards with flatness and smoothness on the upper surface or both the upper and lower surfaces of the multi-layer eucalyptus board, including poplar board, fir board and beech board.

6. The method of claim 1, wherein the inorganic fire retardant comprises one of aluminum hydroxide, antimony trioxide, magnesium hydroxide and microencapsulated red phosphorus; the organic flame retardant is one of tributyl phosphate, tris (2-carbonyl ethyl) phosphate, phosphite ester LM-K1500 and melamine.