Classifications

• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
  • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
  • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
  • E04B1/92—Protection against other undesired influences or dangers
  • E04B1/94—Protection against other undesired influences or dangers against fire
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27D—WORKING VENEER OR PLYWOOD
  • B27D1/00—Joining wood veneer with any material; Forming articles thereby; Preparatory processing of surfaces to be joined, e.g. scoring
  • B27D1/04—Joining wood veneer with any material; Forming articles thereby; Preparatory processing of surfaces to be joined, e.g. scoring to produce plywood or articles made therefrom; Plywood sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L97/00—Compositions of lignin-containing materials
  • C08L97/02—Lignocellulosic material, e.g. wood, straw or bagasse
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
  • B27K2240/00—Purpose of the treatment
  • B27K2240/30—Fireproofing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
  • B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
  • B27K3/16—Inorganic impregnating agents
  • B27K3/166—Compounds of phosphorus
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
  • B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
  • B27K3/16—Inorganic impregnating agents
  • B27K3/20—Compounds of alkali metals or ammonium
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2201/00—Properties
  • C08L2201/02—Flame or fire retardant/resistant
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L61/00—Compositions of condensation polymers of aldehydes or ketones; Compositions of derivatives of such polymers
  • C08L61/04—Condensation polymers of aldehydes or ketones with phenols only
  • C08L61/06—Condensation polymers of aldehydes or ketones with phenols only of aldehydes with phenols
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L61/00—Compositions of condensation polymers of aldehydes or ketones; Compositions of derivatives of such polymers
  • C08L61/20—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
  • C08L61/22—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with acyclic or carbocyclic compounds
  • C08L61/24—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with acyclic or carbocyclic compounds with urea or thiourea
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L61/00—Compositions of condensation polymers of aldehydes or ketones; Compositions of derivatives of such polymers
  • C08L61/20—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
  • C08L61/30—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic and acyclic or carbocyclic compounds
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S428/00—Stock material or miscellaneous articles
  • Y10S428/92—Fire or heat protection feature
  • Y10S428/921—Fire or flameproofing
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31855—Of addition polymer from unsaturated monomers

Definitions

• Fire resisting wooden building articles are prepared by adhering thin pieces of wood under heat and compression with an adhesive comprising synthetic resin, koalin and diammonium phosphate, the pieces of Wood having been previously impregnated with diammonium phosphate.
• the building articles may be in a variety of forms, such as boards or panels, the latter being based on veneers prepared from single pieces of Wood or from plural pieces of Wood, e.g. chips or shavings.
• the present invention relates to a method of producing a fire resisting wooden building article having particularly high fire resisting properties compared with hitherto known fire resisting wooden articles.
• An object of the invention is to provide a method of producing fire resisting wooden building articles, such as boards or panels, based on veneer and capable of resisting high temperatures for a long period without burning through and without through holes being formed in the board when it is burned through and its rear side begins to char.
• an improved fire resisting wooden construction board or the like can be prepared when pieces of veneer, such as shavings or veneer plates, are dried, then impregnated with diammonium phosphate ((NH HPO and thereupon glued together under heating and pressing by means of an adhesive comprising a synethic resin, koalin and diammonium phosphate.
• diammonium phosphate (NH HPO and thereupon glued together under heating and pressing by means of an adhesive comprising a synethic resin, koalin and diammonium phosphate.
• the resin will not only harden but will also react with the diammonium phosphate.
• the resistance of each piece of veneer against heat and flame is thus substantially increased so that any charring of the veneer takes a long time; after charring, the veneer remains united without peeling apart.
• the great heat insulating property in coke further contributes to a delay of the burning through and consequently to an increase in the fire resistance.
• the kaolin in the adhesive has a heat distributing effect whereby local superheating Within the connections between the veneer pieces and thus limited local burning through of the veneer pieces is avoided.
• a 25 mm.-thick plywood board produced by the method of the present invention and at temperatures and pressures normal for the production of plywood boards, i.e. temperatures of between 70 and 150 C. and a pressure of 4-30 kg./m. is capable of resisting the aforesaid flame influence for at least 60 minutes, after which time the rear side of the plate may start charring, but without through holes appearing in the wood.
• the board offers a good resistance to the spreading of a fire.
• a further increase of the fire resisting properties may be obtained if, in addition to the diammonium phosphate, the veneer pieces are impregnated with copper sulphate (CuSO,) which has proved to have a heat distributing effect within veneers, whereby the danger of local super heating is further reduced. Said addition of copper sulphate further causes the board to become resistant against rot, fungus, and vermin attacks.
• CuSO copper sulphate
• the content of kaolin and diammonium phosphate in the adhesive may vary within rather wide limits, inter alia depending on the type of synthetic resin used and the solvent or emulgation agent employed for the adhesive. If, as most often is the case, an aqueous adhesive solution is used, it has been found that the best results are obtained when the adhesive solution has a content of 30 to 50% synthetic resin, 20 to 50% kaolin and 0.5 to 2% diammonium phosphate. Preferably a solution is used having a content of about 40% synthetic resin, 1% diammonium phosphate and 25% kaolin.
• the synthetic resin may be of different types.
• good results have been obtained by using urea formaldehyde together with melamine powder, for example in a proportion of 4:1 by weight, phenolformaldehyde with or without the addition of melamine powder, melamine formaldehyde and epoxy-adhesives.
• the veneers are evenly impregnated with the impregnating agent employed, that is diarnmonium phosphate alone or together with copper sulphate or other substances, and so that at least 30%, preferably about 100% of the pore cavities of the veneer are filled with salts.
• an aqueous diammonium phosphate solution with a content of 15 to 40 percent by weight of diammonium phosphate is used.
• the solution used for the impregnation may have a content of between 0.5 and 3% copper sulphate. If the impregnating solution contains less than 0.5% copper sulphate, there will be no improvement of the fire resistance, and an increase in the content of copper sulphate beyond 3% will cause no further increase in the fire resistance, and, therefore, it will be bad economy to use larger quantities.
• a plywood board or panel produced by the method of the present invention has particularly good fire resisting properties
• a compact board or panel which not only has a particularly great strength, as Well as good nail and screw holding properties, resistance to moisture and direct influence from water as well as to boiling, but which further has quite extraordinarily high fire resisting properties compared to known plywood boards or panels.
• An increase of the fire resisting properties of the board due to high compression of the veneers is obtained by use of a pressure as low as 100 kg./cm. but preferably depending on the species of the wood pressures above 250 kg./cm. ought to be used.
• Example 1 Twenty-one equally large beech veneer plates of a thickness of 1 mm. are dried in a drying oven to a moisture content of 4%, Whereafter the veneers are, in hot condition, placed in a vacuum tank, which is pumped almost empty of air. Thereafter a 30% aqueous solution of diammonium phosphate is let into the tank, and after some time the tank is drained and then opened, and the veneer plates are taken out and again placed in the drying oven, where they are dried to a moisture content of about 610%.
• An aqueous adhesive solution is prepared, consisting of 125 parts by weight of phenol-formaldehyde, 3 parts by weight of diammonium phosphate, 75 parts by weight of kaolin and 97 parts by weight of water.
• the dried impregnated veneer plates are placed on top of each other, every second plate being provided with a 0.2 mm. thick layer of the said adhesive solution on both its sides, whereafter the veneer pile is placed in a press heated to 125 C., and is compressed under a pressure of about 30 kg./cm. for the production of a 25 mm.-thick plywood panel.
• the mechanical properties and resistance of the latter against moisture are the same as the corresponding properties of an ordinary plywood board in which the veneers are glued together by means of phenol-formaldehyde, but contrary to what is the case with such a board, the panel produced according to the example cannot burn and will not, when heated, be able to develop inflammable gases. If, however, its one side is exposed to the flame from a butane gas blow burner, it will become charred, but the said charring will penetrate so slowly through the plate that complete charring will not take place until after a flame influence for a time of 60 minutes or more. Even after such complete charring, the plate will remain intact and not show through holes, just as there will be no peeling off from the charred places.
• Example 2 Forty-five 1 mm.-thick veneer plates are impregnated with diammonium phosphate in the manner stated in Example I, however, by the use of a 25% aqueous solution of diammonium phosphate, and are then dried to a moisture content of about 610%
• An adhesive is prepared by mixing 100 parts by weight of ureaformaldehyde, parts by weight of melamine powder, 3 parts by weight of diammonium phosphate, 75 parts by weight of kaolin and 97 parts by weight of water.
• the forty-five veneers are piled on top of each other, a 0.2 mm. thick layer of said adhesive being applied to every second veneer on both sides thereof, whereafter the pile formed is placed in a press.
• the latter is heated to a temperature of between 110 and 125 C., for example 115 0., and is caused to exert a pressure on said pile of about 300 kg./cm. which compresses the veneers to such an extent that their thickness decreases up to 50%.
• the veneer pile is kept in the press under these conditions for a period of 1620 minutes, and the result is a plywood board of a thickness of 25 mm.
• This board has quite extraordinary mechanical properties both as regards strength and nail and screw holding properties. Moreover, said plate is completely resistant to any form of moisture influence, and to moist air at relatively high temperatures as may be found in tropical countries.
• the board or panel will, however, also have a fire resistance that far exceeds what has hitherto been obtainable even with the use of fireproof materials in the production of fire resisting wooden boards.
• a board will, when influenced by a butane gas blow burner, only show a beginning charring on its rear side after a constant flame influence over a period of more than 150 minutes. Even at that time, the board will remain completely intact showing no peeling and only showing a comparatively slight bulging.
• the charred part will be distinctly limited to the Zone directly hit by the flame, and the charring will have taken place without any appreciable development of smoke.
• Example 3 Following the procedure of Example 2, fifteen veneers are used to prepare a compressed plywood board of a thickness of 10 mm.
• the latter has the same mechanical properties as the board produced according to Example 2, but has, on account of its smaller thickness, a lower fire resistance.
• the 10 mm. thick board will, however, be able to resist the said flame influence for 50-60 minutes.
• Example 4 Thirty-four equally large plate-shaped veneers of a thickness of 1.4 mm. were dried in a drying oven to a moisture content of about 5%, whereafter the veneers were, in hot condition, placed in two vacuum tanks, seventeen in each tank. The tanks were pumped almost empty of air, whereafter an aqueous solution was introduced into the first tank containing 20% diammonium phosphate and 0.5% polyethylene glycol, while an aqueous impregnation solution of 20% diammonium phosphate, 1.5% copper sulphate and 0.5% polyethylene glycol was let into the second tank. After some time the two tanks were drained and opened, and the two sets of differently impregnated veneers were taken out and again placed in the drying oven, where they were dried to a moisture content of about 6%.
• An adhesive was prepared by mixing parts by weight of phenolformaldehyde, 10 parts by weight of para-formaldehyde, 5 parts by weight of diammoniumphosphate, 50 parts by weight of kaolin and parts by weight of water.
• the seventeen veneers of each set were piled on top of each other, every second plate having applied on each side thereof a layer of adhesive about 0.2 mm. thick Whereafter the two piles thus formed were placed in a press.
• the latter was heated to a temperature of about C. and actuated on the piles with a pres sure of about 100 kg./cm.
• the veneers remained under these conditions in the press for a period of 20 minutes, and two plywood boards were formed each having a thickness of about 22 mm.
• each of said two boards was, at its center, exposed to the flame of a butane gas burner under exactly the same conditions. It was found that the board that had only been impregnated by diammonium phosphate was able to resist the flame influence between 1% and 1% hours before any charring appeared on the rear side of the board, whereas the board, the veneers of which were treated with copper sulphate in addition to diammonium phosphate, did not show any charring on the rear side until after 1% hours.
• the method according to the invention has been explained in connection with plywood boards or panels based on plate-shaped veneers, that is in the same manner as is used in the production of plywood and corresponding boards or panels.
• the new method may also be used for the production of fire resisting boards or panels made from shavings or similar small pieces of veneer and will, in connection with such boards, give the same fire retarding effect as has been explained above.
• a method of producing a fire resisting wooden building article from thin pieces of wood comprising drying the thin pieces of wood, impregnating said pieces with diammonium phosphate ((NH HPO and gluing said pieces together under heat and pressure with an adhesive comprising synthetic resin, kaolin and diammonium phosphate.
• diammonium phosphate (NH HPO and gluing said pieces together under heat and pressure with an adhesive comprising synthetic resin, kaolin and diammonium phosphate.
• the adhesive is an aqueous solution comprising 30 to 50% synthetic resin, 20 to 50% kaolin and 0.5 to 2% diammonium phosphate.
• a method according to claim 1 wherein the adhesive comprises, in addition to the synthetic resin, about 1% diammonium phosphate and 25% kaolin.
• the synthetic resin comprises a mixture of a ureaformaldehyde resin and melamine powder.
• a method according to claim 1 wherein the synthetic resin comprises a phenolformaldehyde resin.
• syn thetic resin comprises a melamineformaldehyde resin.
• a method according to claim 1 further comprising impregnating said pieces of wood with copper sulphate (CuSO proir to gluing said pieces together.
• a method according to claim 1 comprising sequentially drying said pieces of wood in a drying oven to a moisture content below 10%, placing said pieces, while still hot, in a vacuum tank, evacuating said vacuum tank, charging said tank with an impregnating liquid comprising diammonium phosphate, removing said pieces from said tank when the former are impregnated, drying the impregnated pieces in a drying oven to a moisture content below 10% and gluing said pieces under heat and pressure with said adhesive.
• the impregnating liquid includes copper sulphate (CuSO for distributing the heat among the pieces of wood in the wooden building article and for reducing the danger of local superheating therein when said article is exposed to flame.
• CuSO copper sulphate
• a wooden board comprising plural diammoniumphosphate-impregnated thin pieces of wood adhered to gether by a synthetic resin adhesive comprising kaolin and diammonium phosphate.

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• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Architecture (AREA)
• Wood Science & Technology (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Civil Engineering (AREA)
• Electromagnetism (AREA)
• Materials Engineering (AREA)
• Physics & Mathematics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Structural Engineering (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Manufacturing & Machinery (AREA)
• Mechanical Engineering (AREA)
• Forests & Forestry (AREA)
• Chemical And Physical Treatments For Wood And The Like (AREA)
• Veneer Processing And Manufacture Of Plywood (AREA)
• Laminated Bodies (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=26065166

Family Applications (1)

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Cited By (10)

Citations (8)

Family Cites Families (1)

• 1964
  • 1964-12-18 DE DEV27398A patent/DE1294003B/de active Pending
• 1965
  • 1965-03-01 US US3498877D patent/US3498877A/en not_active Expired - Lifetime
  • 1965-03-01 CH CH282265A patent/CH457806A/de unknown
  • 1965-03-03 FR FR7782A patent/FR1425913A/fr not_active Expired
  • 1965-03-03 AT AT185065A patent/AT282178B/de active
  • 1965-03-04 ES ES0310137A patent/ES310137A1/es not_active Expired

Patent Citations (8)

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