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
  • B27K3/52—Impregnating agents containing mixtures of inorganic and organic 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
  • 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
  • B27K3/36—Aliphatic 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
  • 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
  • B27K3/40—Aromatic compounds halogenated
• • 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
  • Y10S428/907—Resistant against plant or animal attack

Definitions

• the present invention relates to the preservation of cellulosic materials, such as wood, plywood, chipboard, hardboard and the like. Such materials are hereinafter termed woody collulosic materials.
• woody collulosic materials Such materials are hereinafter termed woody collulosic materials.
• preservative material is applied to the substrate from an organic solvent.
• preservative agents which are capable of being applied from a water based solution are also liable to be leached out by water.
• preservative compositions which contain compounds in addition to the toxic agent, whose role is to assist in keeping the toxic agent in the cellulosic material. Among such compounds are the water soluble dichromates.
• chromic acid salts of organic bases having at least one straight or branched chain containing at least 6 carbon atoms into solvent based preservative compositions, an improved permanency of chlorinated phenols and their salts in the cellulosic material may be obtained.
• These chromic acid salts are able to reduce or suppress, depending on their proportion in the composition, the loss of chlorinated phenols from the cellulosic materials by evaporation, especially at slightly elevated temperatures such as 50 C. They are also able to reduce the ease with which chlorinated phenols can be leached from the cellulosic materials by water.
• the resistance to water leaching may be further enhanced if the cellulosic material is aged at slightly elevated temperatures (for example, for 1 week at 50 C.) after impregnation with the composition.
• slightly elevated temperatures for example, for 1 week at 50 C.
• Two of the practical advantages arising from these effects are the following. Protection of woody cellulosic material initially containing the amount of chlorinated phenols normally employed will be longer-lasting, especially in hot countries, in the presence of these chromic acid salts, because the loss of preservative as time goes on will be less.
• the present invention provides a process for preserving woody cellulosic materials which comprises applying to the material an organic solvent solution of a chlorinated phenol having one or more hydroxy groups bound to a benzene ring and from 1 to 5 chlorineatoms bound to the same benzene ring which is optionally substituted by one or more hydrocarbon groups or a salt of such a phenol soluble in the solvent, and a salt of chromic acid with an organic base, which is sufiiciently soluble in the solvent to provide a solution containing at least 0.2% w./v. CrO (equivalent) at 20 C. which contains at least one straight or branched chain containing at least 6 carbon atoms.
• the process may be carried out by applying the chlorinated phenol or its salt to the wood either in the same solution as the chromium compound, or in a different solution either before or after the application of the chromium compound.
• the invention provides a composition suitable for the treatment of woody cellulosic materials which comprises an organic solvent having dissolved therein a chlorinated phenol as above defined or a salt thereof, and a salt of chromic acid with an organic base sufficiently soluble to provide a solution containing at least 0.2% w./v. CrO (equivalent) at 20 C. and having at least one branched or straight chain containing at least 6 carbon atoms.
• Suitable salts of chromic acid with organic bases for use in the present invention are those which are sufiiciently soluble in the solvent employed to provide a solution containing at least 0.2% w./v. CrO (equivalent) at C.
• the preferred organic bases are those which contain branched chains, which may consist solely of carbon atoms or may also contain nitrogen atoms.
• the organic bases are primary, secondary and tertiary amines, quaternary ammonium bases, substituted guanidines, biguanides, and s-triazines possessing at least one branched chain in the molecule.
• Particularly suitable types of base are secondary and tertiary alkyl primary amines having from 6 to 22 carbon atoms in the alkyl group, in which the amino group is joined to a carbon atom which is itself attached to two or three alkyl groups, respectively.
• Other useful compounds are the guanidine derivatives of such amines.
• Particular bases which are preferred for the present invention are Z-ethyI-n-hexyl amine, di-(Z-ethyl-n-hexyl) amine, tri-(3,5,5-trimethyl-n-hexyl) amine, the mixture of tertiary alkyl primary amines containing from twelve to fourteen carbon atoms known as Primene 81-R (the word Primene being a registered trademark), the mixture of tertiary alkyl primary amines containing from eighteen to twenty-two carbon atoms known as Primene JM-T, the mixture of secondary alkyl primary amines derived from n-undecane known as Armeen L.l1 (the word Armeen being a trademark).
• Other useful compounds include 2,4,6 tris-(2 ethyl n hexylarnino)-striazine the mixed 1,5-dialkyl biguanides derived from Primene" 8l-R or Primene JM-T, and the mixed, N,N',N"-trialkyl guanidines derived from Primene 81R or Primene JM-T.
• hexavalent chromium salts suitable for use in the present invention are chromates and dichromates which are frequently of the composition B H CrOl, or
• salts for use in the invention include all organic base/chromic acid salts which have the appropriate solubility characteristics as defined above and that such salts can be used according to the invention either singly or in admixture with each other or one another. It will also be understood that bases which are too easily oxidised by chromic acid, and salts which too easily decompose by internal oxidation-reduction reactions, are to be avoided.
• Preservative agents which are of use in the present invention are chlorinated phenols and their solvent-soluble salts. Such compounds contain one or more hydroxyl groups bound to a benzene ring and from 1 to 5, preferably 3 to 5, chlorine atoms bound to the same benzene ring.
• the benzene ring may however, be substituted by one or more hydrocarbon groups such as alkyl groups having from 1 to 6 carbon atoms or aromatic groups.
• Compounds which may be employed include the tri and tetrachloro cresols, chlorinated bis phenol A, the trichloro xylenols, tetrachloro ortho phenyl phenol and chlorinated hexyl phenols.
• the preferred compounds are tri, tetra and penta chlorophenols, especially penta chloropheuol.
• salts of chlorinated phenols it is understood that they will be compatible with the chromic acid salt, as for example when the salt of the chlorinated phenol and the chromic acid salt are derived from the same organic base.
• preservative agents commonly used in solventbased wood preservative compositions may also be included in the compositions if desired, such biocidal compounds include for example copper naphthenates, solubilised copper 8-quinolinolate and triorganotin compounds such as tributyltin oxide and its derivatives.
• Solvent soluble salts of arsenic acid with suitable organic bases such as #Primene 81-R and Primene J-MT may also be employed. All these materials may have their own permanency in woody cellulosic materials improved 4 when they are employed in the presence of a hexavalent chromium compound.
• Suitable solvents for use according to the invention include aromatic hydrocarbons such as xylene and aromatised petroleum distillates, petroleum hydrocarbon solvents, and mixtures of petroleum hydrocarbon solvents with aromatic hydrocarbons and/or ketones. It is desirable that the solvent should either not react at all, or react only very slowly, with the chromic acid salt at temperatures of less than 30 C.
• the chlorinated phenol will normally be present in an amount depending on such factors as the degree of protection and the degree of penetrability desired, and the cost of the solvent. Typically it will provide from 0.5 to 10% of the total composition.
• the chromic acid salts will be used in amounts which will fix substantially all of the preservative, or only a part of it, whichever may be desired. The amount required will vary according to the nature of the preservative and its own concentration in the preservative composition and the degree of fixation desired but normally will lie within the concentration range 05-50% and is often preferably in the range 12S% of the total composition.
• 'Cellulosic materials may be treated with the compositions as described above by any convenient method.
• the desired composition may be applied to the wood by brushes or rollers, or the wood may be dipped int the preservative solution.
• a further method by which impregnation may occur is by exposing the material to be treated to a solution of desired composition under pressure, for example by evacuating a vessel containing the material, covering the material with the solution, and then restoring the pressure to atmospheric.
• compositions of the invention may also contain other substances which commonly occur in solvent-based compositions employed for the preservation of woody cellulosic materials; for example, insecticidal compounds such as lindane and anti-blooming agents (which prevent the formation of deposits of solid chlorinated phenols on the surface of the cellulosic material) such as dibutyl phthalate.
• insecticidal compounds such as lindane and anti-blooming agents (which prevent the formation of deposits of solid chlorinated phenols on the surface of the cellulosic material) such as dibutyl phthalate.
• compositions for use in the present invention are illustrated by the following examples:
• EXAMPLE 1 Four preservative formulations (A, B, C and D) were prepared from the following quantities (in parts by weight) of pentachlorophenol, Primene Sl-R dichromate, and xylene, respectively: A-5,0,95; B-5,5,90; C- 5.7,88; and D5,10,85. Pinewood strips, 25 mm. x 5 mm. x 1.6 mm., were impregnated with these formulations by a simple vacuum-pressure technique. The strips were contained in a vessel, which was pumped down to a pressure of 15 mm.; of mercury. After 30 minutes of continuous pumping, the vessel was isolated from the pump, the strips were covered with one of the above formulations, and atmospheric pressure was restored. After soaking in the liquid for 2 hours, the strips were removed and allowed to drain on absorbent paper. They were then allowed to stand at the ordinary temperature until all the xylene had evaporated.
• the pentachlorophenol content of the impregnated strips was determined by boiling a sample (about 0.5 gm.) with 0.1 N-sodium hydroxide (250 ml.) for 3 hours. This process extracts all the pent-achlorophenol and any unreduced hexavalent chromium from the wood. The extract was acidified and extracted with xylene, and the pentachlorophenol content of the xylene extract de termined colorimetrically by the 4-amino-antibyrine/ ferricyanide method of Goto, Kawahara and Sato (Analytical Abstracts No. 577 3 (1964)).
• a preservative formulation (E) was prepared from pentachlorophenol parts by weight), Z-ethyl-n-hexylamine chromate (9.4 parts), and xylene (85.6 parts). Pinewood strips were impregnated with formulations A and E, dried at the ordinary temperature, and samples analysed for their pentachlorophenol content, all as in Example 1.
• the strips were placed in an air oven at 50 C., and kept there for 2 weeks. At the end of this time the pentachlorophenol content of the A-treated strips had fallen from its initial value of 71.4 mg./g., of wood to 8.4 mg./ g., corresponding to an evaporation loss of 89%, whereas in the case of the E-treated strips the fall was from 65.6 mg./g., to 61.1 mg./g., corresponding to an evaporation loss of only 7%.
• EXAMPLE 4 A preservative formulation (F) was prepared from 2. 4,6-trichlorophenol (3.7 parts by weight) and xylene (96.3 parts), and another one (G) from 2,4,6-trichlorophenol (3.7 parts), Primene 8l-R dichromate (7.5 parts), and xylene (88.8 parts). Pinewood strips were impregnated with these two formulations, dried at the ordinary temperature, and samples analysed for their trichlorophenol content by the same method as was used for pentachlorophenol, all as in Example 1.
• the strips were placed in an air oven at 50 C., and kept there for 1 week. At the end of this time the trichlorophenol content of the F-treated strips had fallen from its initial value of 21.3 mg./g., of wood to zero, corresponding to an evaporation loss of whereas in the case of the G-treated strips the initial trichlorophenol content of the wood remained unchanged at 22 mg./g., corresponding to zero evaporation loss.
• G-treated strips after keeping for 1 week at 50 C., were extracted 25 times with warm water in a Soxhlet extractor, when the trichlorophenol content of the wood fell from 22.0 mg./g., to 11.0 mg./g.
• a process for preserving woody cellulosic materials of wood, plywood, chipboard or hardboard which comprises applying to the material an organic solvent soluion containing (i) from 0.5 to 10% by weight of a chlorinated phenol having one or more hydroxy groups bound to a benzene ring and from 1 to 5 chlorine atoms bound to the same benzene ring which is optionally substituted by one or more hydrocarbon groups or a salt of such a phenol soluble in the solvent, and (ii) from 1 to 50% by weight of a salt of chromic acid with an organic base which contains at least one straight or branched chain containing at least 6 carbon atoms, said salt having a solubility in the solvent sufficient to provide a solution containing at least 0.2% w./v. CrO (equivalent) at 20 C.
• chlorinated phenol employed is selected from the group comprising trichlorophenol, tetra chlorophenol, penta chlorophenol and mixtures thereof.
• a process as claimed in claim 1 wherein the salt of chromic acid employed is a salt of a secondary tertiary alkyl primary amine having from 6 to 22 carbon atoms.
• the chromic acid salt employed is a salt of an amine selected from the group comprising 2-ethyl-n-hexyl amine, di(2-ethy1-nhexyl) amine, tri(3,5,5 trimethyl-n-hexyl) amine, a mixture of tertiary alkyl primary amines containing from 12 to 14 carbon atoms, a mixture of tertiary alkyl primary amines containing from 18 to 22 carbon atoms and a mixture of secondary alkyl primary amines derived from nundecane.
• an amine selected from the group comprising 2-ethyl-n-hexyl amine, di(2-ethy1-nhexyl) amine, tri(3,5,5 trimethyl-n-hexyl) amine, a mixture of tertiary alkyl primary amines containing from 12 to 14 carbon atoms, a mixture of tertiary alkyl primary amines containing from 18 to
• said organic solution comprising a chlorinated phenol selected from the group comprising tri, tetra and penta chlorophenols and their solvent soluble salts and a salt of chromic acid with an amine selected from the group comprising 2-ethyln-hexyl amine, di(2-ethyl-n-hexyl) amine, tri(3,5,5-trimethyl-n-hexyl) amine, a mixture of tertiary alkyl primary amines containing from 12 to 14 carbon atoms, a mixture of tertiary primary amines containing from 18 to 22 carbon atoms and a mixture of secondary alkyl primary amines derived from n-undecane.
• an amine selected from the group comprising 2-ethyln-hexyl amine, di(2-ethyl-n-hexyl) amine, tri(3,5,5-trimethyl-n-hexyl) amine, a mixture of tertiary

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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)
• Agricultural Chemicals And Associated Chemicals (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=10375004

Family Applications (1)

Country Status (10)

Cited By (4)

• 1968
  • 1968-07-23 GB GB35200/68A patent/GB1270659A/en not_active Expired
• 1969
  • 1969-07-18 NO NO3007/69A patent/NO123834B/no unknown
  • 1969-07-21 NL NL6911141A patent/NL6911141A/xx unknown
  • 1969-07-22 DE DE19691937226 patent/DE1937226A1/de active Pending
  • 1969-07-22 CH CH1119569A patent/CH518784A/de not_active IP Right Cessation
  • 1969-07-22 US US843771A patent/US3702784A/en not_active Expired - Lifetime
  • 1969-07-22 SE SE10335/69A patent/SE344553B/xx unknown
  • 1969-07-22 FR FR6924980A patent/FR2013533A1/fr not_active Withdrawn
  • 1969-07-23 BE BE736455D patent/BE736455A/xx unknown
  • 1969-07-23 AT AT712469A patent/AT291525B/de not_active IP Right Cessation

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