Classifications

• • 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
  • B27K3/02—Processes; Apparatus
  • B27K3/0278—Processes; Apparatus involving an additional treatment during or after impregnation
  • B27K3/0292—Processes; Apparatus involving an additional treatment during or after impregnation for improving fixation
• • 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
  • B27K3/26—Compounds of iron, aluminium, or chromium
• • 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
  • B27K3/34—Organic impregnating agents
  • B27K3/38—Aromatic compounds
• • 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
  • B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
  • B27K5/001—Heating
• • 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
  • B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
  • B27K5/007—Treating of wood not provided for in groups B27K1/00, B27K3/00 using pressure
• • 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
  • B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
  • B27K5/02—Staining or dyeing wood; Bleaching wood

Definitions

• the present invention relates to a method for treating at least one piece of wood, a piece of wood obtained by said method.
• the fir In the natural state, the fir has a hardness of 10 to 15 N / mm 2 , while the quebracho, the hardest solid wood in its natural state has a hardness of 102N / mm 2 . In comparison, aluminum commonly used for industrial applications has a hardness of 150N / mm 2 . Thus, if one wishes to replace certain metals with wood, it is necessary
• Impregnation techniques are known which make it possible to give a hue to the wood.
• the known techniques are limited to a surface impregnation, only a few millimeters. These techniques make it possible to manufacture colored veneers which can cover a piece of wood, for example in densified wood, but these techniques are very expensive and do not give the same result as a colored wood in one piece.
• An object of the present invention is to provide a wood treatment process free or that minimize the limitations of known methods. According to the invention, these objects are at least partially achieved by means of a method for treating at least one piece of wood.
• a densification phase comprising: i) compressing said part by exerting a first pressure at a first temperature and then a second pressure at a second temperature, the second temperature and the second pressure being respectively lower than the first temperature and at the first pressure.
• This solution has the advantage over the prior art of providing a densified wood piece having improved physical and / or mechanical and / or visual and / or aesthetic properties compared to the parts obtained with known treatment.
• the process according to the invention makes it possible to obtain parts having a remarkable density, for example between 1000 kg / m 3 and 1500 kg / m 3 , preferably between 1300 kg / m 3 and 1400 kg / m 3 .
• the process according to the invention makes it possible to obtain a densified wood having an integral and homogeneous coloration in the mass of the wood.
• the stoving phase is a step that makes it possible to make the transition between an impregnation stage and a densification stage.
• the stoving stage makes it possible to improve the quality of the coloring of the densified wood compared to the existing methods.
• the method of the invention improves the durability of the color of the piece of wood.
• the coloring of the parts treated by the process according to the invention is more persistent in case of leaching compared to the parts treated with the existing methods.
• the method according to the invention makes it possible to obtain a densified and colored wood having an improved hardness, for example between 100 N / mm 2 and 200 N / mm 2 , preferably between 140 N / mm 2 and 170 N / mm 2 .
• the method according to the invention makes it possible to treat parts of all sizes: for example parts having dimensions of the order of a millimeter, centimeter, or even the meter.
• the method of the invention allows to control the thickness of the piece of wood after densification.
• a shim or a mold to define the minimum height of the part.
• the piece of wood is impregnated with at least one coloring agent.
• the coloring agent comprises a first reagent solution and a second reagent solution.
• the coloring agent, the first reagent solution or the second reagent solution may be soluble in an organic solvent (in a solvent phase) or in an aqueous phase (soluble in an aqueous medium).
• the coloring agent, the first reagent solution or the second reagent solution may be reactive with wood or air to give a color, or simply be an inert dye which does not interact with the wood or the environment in which it is located.
• the impregnation phase can be carried out using a conventional impregnation method known to those skilled in the art, for example: soaking, immersion (long-time soaking), vacuum impregnation, pressure impregnation pressure injection, end-grain injection and the various combinations of these impregnation methods, such as impregnation under vacuum and alternating pressure for example. Impregnation may also include diffusion, perforation, painting, spraying.
• the impregnation, stoving and densification phases are successive phases.
• the impregnation, steaming and densification phases are simultaneous phases.
• the impregnation phase is the impregnation phase
• Impregnating said part comprises: i) Impregnating said part with a first reagent solution; ii) Impregnating said part with a second reagent solution;
• impregnation comprises the use of at least two reagent solutions.
• the first reagent solution may be different or identical to the second reagent solution.
• a coloring agent is applied which comprises several reagent solutions on the wood, for example a first reagent solution and a second reagent solution.
• the reagent solutions can react with each other and the product of this reaction can act on the wood to be treated.
• the reagent solutions are applied successively to the wood.
• the reagent solutions are applied at the same time to the wood to be treated.
• said coloring agent or said first reagent solution comprises between 0.1% by weight and 10% by weight of fixing agent, preferably between 0.1 and 5% by weight, in particular between 0.4% by weight. and 1% by weight.
• a reagent solution that contains an agent Fixant makes it possible to degrade the bonds between the chemical components of the wood, for example the wood fibers.
• the first reagent solution or said coloring agent comprises an acid having a pka of less than 5, preferably less than 3.
• the fixing agent is an acid having a pka less than 5, preferably less than 3.
• the acid is a phenolic acid.
• phenolic acid is used in the case where the wood subjected to the process naturally contains little or no phenolic compound such as hydrolysable tannins
• the first reagent solution or said coloring agent comprises at least one fixing agent chosen from gallic acid, oak tannins, chestnut tannins, or any other composition comprising a phenolic acid.
• the first reagent solution or said coloring agent comprises 0.6% by weight of gallic acid.
• the impregnation phase comprises
• the piece of wood in the impregnation phase is impregnated with a second reagent solution.
• the second reagent solution can make it possible to color the piece of wood, by reacting with the first reagent solution or with the phenolic compounds already present in the wood in the case of treating a gasoline containing naturally enough.
• the first reagent solution and the second reagent solution may have a complementary action, for example when the dye product results from the reaction between the first reagent solution and the second reagent solution.
• the components of the second reagent solution for example minerals or pigments, may interact with the wood fibers, for example by attaching to the structural components of the wood (eg fibers).
• the coloring product makes it possible to stabilize the structure of the wood after impregnation. This minimizes
• the part is not dried between the impregnation with the first reagent solution and the impregnation with the second reagent solution.
• the second reagent solution or said reactive dyeing agent comprises at least one dye, for example a pigment.
• the second reagent solution or the coloring agent comprises at least one dye chosen from ferrous compounds, for example iron (II or III) sulphate, iron (II or III) chloride, or any other compound ferrous dye.
• the second reagent solution or the coloring agent comprises 2% by weight of ferrous dye compound, for example iron (II) or (III) sulfate.
• said second reagent solution or the coloring agent comprises between 0.1% by weight and 10% by weight of said pigment or dye, preferably between 1 and 5% by weight, in particular between 1.5% by weight. and 3% by weight.
• a second reagent solution under vacuum for 2 hours to 20 hours, preferably between 8 am and 14 pm, in particular between 1 hour and 13 pm.
• the inventors have noticed that an impregnation of said part with a second reagent solution for 12 hours
• the method according to the invention comprises a stoving phase.
• the stoving phase comprises: i) heating said part in the presence of saturating steam;
• this heating can be achieved by placing the room in an autoclave.
• the steam allows to conduct heat in the voids present between the fibers of the piece of wood. This allows a rise in
• the stoving phase also allows homogeneous impregnation in the mass, in particular a homogeneous coloration. This phase can also make it possible to increase the reaction between the solution or the reagent solutions and the wood fibers thanks to the presence of saturating water vapor and heat. This phase is used to prepare the wood for densification.
• the parboiling phase comprises
• the densification phase further comprises:
• Wood is made up of polysaccharides such as hemicellulose, cellulose, or other polymers such as lignin that interact with each other to form a flexible, shape-memory structure in their natural state.
• hydrolysis of the hemicelluloses constituting the wood fibers is observed in particular.
• hemicelluloses are particularly involved in the shape memory of wood fibers: hemicelluloses interact mainly with water and resume their initial position on contact (ie shape memory).
• hydrolysis of hemicelluloses contributes to the loss of shape memory of the part, which is thus more stable in a variable hygrometric environment.
• the first pressure is reached by increasing the pressure continuously, that is to say increasing the pressure without stopping until the first pressure is reached. This also applies to reach the first temperature, mutatis mutandis.
• the first pressure it is possible to reach the first pressure by increasing the pressure discontinuously, that is to say by increasing the pressure by marking downtime at one or more levels. This also applies to reach the first temperature, mutatis mutandis.
• the densification phase is the densification phase
• a first pressure of between 15 MPa and 20 MPa on said part preferably between 16.5 MPa and 18.5 MPa, by heating said part to a first temperature of between 150 ° C. and 180 ° C., preferably between 160 ° C. and 170 ° C. ° C, for 10 minutes to 1 hour,
• a first pressure of between 16.5 MPa and 18.5 MPa by heating said part to a first temperature of between 160 ° C. and 170 ° C. for 15 minutes to 25 minutes, provided particularly good results. satisfactory.
• a second pressure of between 7 MPa and 9 MPa on said part by heating said part to a second temperature between 15 ° C and 25 ° C, for between 30 min and 50 min. provided particularly good results
• the first and the second pressure are performed by mechanical action, for example using a platen hydraulic press, for example heated platens.
• the first and the second pressure are made in the radial direction of said part.
• An embodiment where the first and second pressures are made in the tangential direction is also possible.
• the wood of the piece of wood is selected from beech, white fir, spruce, maple, basswood, ash, and any other compatible species deemed local in Europe.
• the method for treating at least one piece of wood comprises:
• an impregnation phase comprising: i) impregnating said piece with a first reagent solution for 1 hour to 13 hours under vacuum, said first reagent solution comprising between 0.4% and 1% by weight of gallic acid; ii) Impregnating said piece with a second reagent solution for 1 hour to 13 hours under vacuum, said second reagent solution comprising between 1.5% and 3% by weight of iron sulfate;
• a stoving phase comprising: i) heating said part in the presence of saturating steam between 135 ° C and 145 ° C, for 50 min to 1 h 10;
• a densification phase comprising: i) compressing said part by exerting a first pressure at a first temperature and then a second pressure at a second temperature, the second temperature and the second pressure being respectively lower than the first temperature and at the first pressure , the first pressure being between 16.5 MPa and 18.5 MPa on said part, by heating said part at a first temperature between 160 ° C and 170 ° C, for 15 min to 25 min. the second pressure being between 7 MPa and 9 MPa on said part by heating said part to a second temperature of between 15 ° C. and 25 ° C. for 30 minutes to 50 minutes.
• the method for treating at least one piece of wood comprises:
• an impregnation phase comprising an impregnation mode chosen from: soaking, immersion or long-time soaking, vacuum impregnation, impregnation under pressure, injection under pressure, wood injection end and the different combinations of these impregnation methods, for example such as alternating vacuum and pressure impregnation.
• a stoving phase comprising: i) heating said part in the presence of saturating steam between 135 ° C and 145 ° C, for 50 min to 1 h 10;
• a densification phase comprising: i) compressing said part by exerting a first pressure at a first temperature and then a second pressure at a second temperature, the second temperature and the second pressure being respectively lower than the first temperature and at the first pressure the first pressure being between 16.5 MPa and 18.5 MPa on said workpiece, by heating said workpiece at a first temperature between 160 ° C and 170 ° C for 15 min to 25 min. the second pressure being between 7 MPa and 9 MPa on said part by heating said part at a second temperature between 15 ° C and 25 ° C for 30 min to 50 min.
• the method comprises: [0052] D) a heat treatment phase comprising the passage of said part in an atmosphere for 1 h to 30 h, preferably between 10 and 20 h, at a pressure ranging from 0 bars at 40 bars, preferably between 1 and 20 bars, said atmosphere comprising: a temperature of between 50 ° C. and 250 ° C., preferably between 100 ° C. and 200 ° C., for example in the oven or in an autoclave, at a relative humidity of between 0 and 100%.
• This heat treatment step makes it possible to improve the dimensional stability of the part and the fixing of the coloring agent.
• the heat treatment step is performed after the densification phase. This allows to increase the rate of production, several parts can undergo heat treatment simultaneously.
• the method comprises an intermediate drying phase between the impregnation of the first reagent solution and the impregnation of the second reagent solution. This removes the liquid portion of the first reagent solution to release the voids in the wood fibers and facilitate the impregnation of the second reagent solution.
• the intermediate drying phase comprises a passage in the oven for 0.25h to 30h, preferably between 1h and 10h in an atmosphere:
• the intermediate drying phase comprises a passage in an autoclave for 0.25h to 30h, preferably between 1h and 10h in an atmosphere: at a temperature between 0 and 100 ° C., preferably between 10 and 30 ° C.,
• process for treating a piece of wood define in particular a method for coloring and densifying a piece of wood.
• the method for treating at least one piece of wood according to the invention can be applied to the treatment of natural fiber-based materials, for example panels based on wood fibers, reed, rattan, bamboo, etc.
• the Bars are used for the atmospheric pressure and the Mpa for the pressing pressure. It is possible to move from one unit to another using the known conversion tables.
• Pieces of beech (Fagus sylvatica L.) of size 40 mm * 65 mm * 60 mm are impregnated under vacuum in a first reagent solution comprising 0.66% by weight of gallic acid for 12 hours.
• the parts have not been dried between the two impregnation phases.
• the densification process is divided into two stages:
• the parts are densified at a first pressure of 17.5 MPa at a first temperature of 165 ° C. This pressure is maintained for approx. 20 min. Then the pressure and the temperature are lowered to 8 MPa (second pressure) and respectively to 20 ° C (second temperature) for 40 minutes, during a second pressure, to cool the parts.
• the method provides a piece of wood with a density of about 1380 kg / m 3 of uniform dark black throughout the entire section of the room.

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• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Forests & Forestry (AREA)
• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Chemical And Physical Treatments For Wood And The Like (AREA)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (2)

Family Cites Families (5)

• 2018
  • 2018-07-09 WO PCT/IB2018/055032 patent/WO2019012403A1/fr unknown
  • 2018-07-09 EP EP18755893.7A patent/EP3651956A1/de active Pending

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