EP0646148A4 - Improved lignin-based wood adhesives. - Google Patents
Improved lignin-based wood adhesives.Info
- Publication number
- EP0646148A4 EP0646148A4 EP19920909872 EP92909872A EP0646148A4 EP 0646148 A4 EP0646148 A4 EP 0646148A4 EP 19920909872 EP19920909872 EP 19920909872 EP 92909872 A EP92909872 A EP 92909872A EP 0646148 A4 EP0646148 A4 EP 0646148A4
- Authority
- EP
- European Patent Office
- Prior art keywords
- adhesive
- phenol
- organosolv lignin
- lignin
- formaldehyde
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J161/00—Adhesives based on condensation polymers of aldehydes or ketones; Adhesives based on derivatives of such polymers
- C09J161/04—Condensation polymers of aldehydes or ketones with phenols only
- C09J161/06—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
- C08L97/00—Compositions of lignin-containing materials
- C08L97/02—Lignocellulosic material, e.g. wood, straw or bagasse
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J197/00—Adhesives based on lignin-containing materials
- C09J197/005—Lignin
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
- C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
- C08L2666/14—Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
- C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
- C08L2666/26—Natural polymers, natural resins or derivatives thereof according to C08L1/00 - C08L5/00, C08L89/00, C08L93/00, C08L97/00 or C08L99/00
Definitions
- Typical phenol " formaldehyde adhesives which are used in the manufacture of structural wood products such as plywood, waferboard, oriented strandboard and fiberboard contain many constituents in addition to the resin.
- various extenders, accelerators, fillers, viscosity control agents and other additives are generally added to the resin to control the properties of the formulation. While some of the added constituents are less costly than the resin itself, phenol-formaldehyde resins are not usually suitable for the formulation of low-value products.
- kraft lignins have been made in phenol-formaldehyde adhesive formulations. Since kraft lignins are relatively unreactive and sinter when heated, they are unsuitable for dry resin applications. Furthermore, when compounded with liquid phenol- formaldehyde resins, kraft lignins yield an over-viscous mixture. To enhance the reactivity of kraft lignins and improve on their potential for cross-linking, methylol groups have been added by reacting kraft lignins with formaldehyde.
- an adhesive for the manufacture of plywood, fiber board, and similar products is described.
- the adhesive is a combina ⁇ tion of phenol-formaldehyde resin, and a lignin derivative such as lignosulfonates or alkali lignins.
- a minimum of 65% by weight of the lignosulfonates and a minimum of 40% by weight of the alkali lignins have relative molecular weights in excess of glucagon.
- a phenol- formaldehyde resin adhesive is formulated in which a portion of the phenol ingredient is replaced with ammonium lignosulfonate.
- organosolv lignin such as ALCELL ® lignin recovered by the process described in U.S. Patent No. 4,746,596 to Lora et al. can effectively compete with lignins produced from conventional processes in many applications.
- ALCELL ® lignin can be used in applications such as the formulation of phenol-formaldehyde lignin- based adhesives.
- This invention provides for adhesives for wood composites comprising an organosolv lignin and a phenol- formaldehyde resin in a weight ratio of from about 0.5:99.5 to about 70:30 based on phenolic solids in said phenol-formaldehyde resin.
- the performance of the adhesive can be improved by the addition of a modifier in a weight ratio with organosolv lignin of from about 0.5:99.5 to about 20:80. Boards manufactured with this particular adhesive have competitive properties.
- the performance of the adhesive can be improved by the addition of a low molecular weight organosolv lignin in a weight ratio with organosolv lignin of from about 5:95 to about 70:30. Boards manufactured with this particular adhesive have competitive properties. In accordance with this invention, the performance of the adhesive can be improved by extending the press time or increasing the press temperature during board manufacture. Boards manufactured with this particular adhesive have competitive properties.
- the performance of the adhesive can be improved by baking and drying the organosolv lignin prior to formulation. Boards manufactured with this particular adhesive have competitive properties.
- a liquid phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 3 and alkali of from about 0.12 to about 0.47 moles per mole of phenol.
- An adhesive can be manufactured comprising organosolv lignin of from about 5:95 to 60:40 based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.
- a liquid phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol.
- An adhesive can be manufactured comprising organosolv lignin of from about 0.5 to about 40% based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.
- a liquid phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.3 to about 3.0, alkali of from about 0.5 to about 0.8 moles per mole of phenol.
- An adhesive can be manufactured comprising organosolv lignin from about 2 to about 30% based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.
- a liquid phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.4 to about 3.5 and alkali of from about 0.4 to about 1 moles per mole of phenol.
- An adhesive can be manufactured comprising organosolv lignin from about 0.8 to about 35% based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.
- low molecular weight organosolv lignin can be used as a partial replacement for phenol in the manufacture of a liquid phenol-formaldehyde resin.
- the low molecular weight organosolv lignin can be added during the preparation of the resin and replace from about 0.5 to about 40% of the phenolic resin solids in the adhesive.
- the phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.
- an alkaline solution of organosolv lignin can be used as a partial replacement for phenol during the manufacture of a liquid phenol-formaldehyde resin.
- the alkaline solution of organosolv lignin can be prepared by addition of alkali of from about 10 to about 25% on a lignin weight basis and can be added to a liquid phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on phenolic solids in the resin.
- the phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 3 and alkali of from about 0.12 to about 0.47 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.
- the alkaline solution of organosolv lignin can be used as a partial replacement for phenol during the manufacture of a liquid phenol-formaldehyde resin and replace from about 2 to about 30% of the phenolic resin solids.
- the phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.3 to about 3 and alkali of from about 0.5 to about 0.8 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.
- an organosolv lignin dispersion can be added to a liquid phenol- formaldehyde resin.
- the dispersion comprises a dispersing agent and organosolv lignin in a weight ratio of from about 0.5:99.5 to about 2:98.
- the organosolv lignin dispersion can be directly added to the resin in a weight ratio of from about 5:95 to about 60:40 based on phenolic solids in the resin.
- the phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 3 and alkali of from about 0.12 to about 0.47 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.
- organosolv lignin can be phenolated by reacting the organosolv lignin of from about 10 to about 80% of total reaction weight with phenol of from about 10 to about 80% of total reaction weight with alkali of from about 1 to about 20% of total reaction weight.
- the phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol.
- the organosolv lignin can constitute for from about 1 to about 45% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.
- organosolv lignin can be phenolated by reacting the organosolv lignin of from about 10 to about 80% of total reaction weight with phenol of from about 10 to about 80% of total reaction weight with alkali of from about 1 to about 20% of total reaction weight.
- the phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.4 to about 3.5 and alkali of from about 0.4 to about 1 moles per mole of phenol.
- the organosolv lignin can constitute from about 1 to about 70% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.
- organosolv lignin can be methylolated by reacting the organosolv lignin of from about 20 to about 60% of total reaction weight with phenol of from about 20 to about 50% of total reaction weight.
- Formaldehyde of from about 5 to about 50% of total reaction weight can be added using an acid of from about 0.01 to about 3% of total reaction weight.
- the phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol.
- the organosolv lignin can constitute from about 1 to about 70% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.
- organosolv lignin can be methylolated by reacting the organosolv lignin of from about 20 to about 60% of total reaction weight with phenol of from about 20 to about 50% of total reaction weight.
- Formaldehyde of from about 5 to about 50% of total reaction weight can be added using an acid of from about 0.01 to about 3% of total reaction weight.
- the phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.4 to about 3.5 and alkali of from about 0.4 to about 1 moles per mole of phenol.
- the organosolv lignin can constitute from about 1 to about 45% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.
- the lignin employed in this invention is an organosolv lignin, preferably ALCELL ® lignin which is the natural product extracted from wood with alcohol and water and is recovered as described in U.S. Patent No. 4,764,596 and U.S. Patent Application Ser. No. 07/649,683 filed February 1, 1991 incorporated by reference herein.
- ALCELL ® lignin is recovered as a free-flowing powder and resembles to a great extent native lignin.
- organosolv lignin such as ALCELL ® lignin can be added in a variety of ways as a substitute for phenol-formaldehyde core and face resins which are suitable in the formulation of adhesives for use in the manufacture of wood composites such as structural and nonstructural wood products including plywood, waferboard, oriented strandboard, particle board, fiber board, hard board and the like.
- ALCELL ® lignin is sulfur-free and has low levels of carbohydrates and inorganic contaminants. It is also highly hydrophobic, is essentially insoluble in neutral or acidic aqueous media, and is soluble in moderate to strong alkaline solutions and certain organic solvents.
- ALCELL ® lignin can be characterized as having: a relatively low number average molecular weight of about 800 to 1500 g/mole, preferably about 900 to 1300 g/mole and a glass transition temperature which is preferably about 100° to 170°C, particularly about 130° to 150°C, although a glass transition temperature of preferably about 80° to 170°C, particularly about 90° to 150°C is also observed; a narrow molecular weight distribution, i.e., a polydispersity of less than about 4, preferably no more than about 3, particularly only about 1.5 to 2.7; and, a methoxyl content approximately equal to the methoxyl content of native lignin (i.e., about 20% for hardwoods and about 14% for softwoods).
- ALCELL ® lignin also has a softening temperature which is preferably about 120° to 150°C, particularly about 130° to 150°C.
- powder phenol- formaldehyde resin and dry organosolv lignin are directly blended in a weight ratio of from about 30:70 to about 95:5, preferably of from about 70:30 to about 85:15.
- the performance of the combination of dry organosolv lignin and powder phenol-formaldehyde resin can be further improved by extending the press time or by increasing the press temperature. Alternatively, baking the organosolv lignin for from about 15 to about 90 minutes and at temperatures of from about 120 to about 200°C or flash drying of the organosolv lignin at a dryer inlet temperature of from about 135° to about 250°C prior to formulation, significantly improves board properties.
- the performance of the organosolv lignin/phenol- formaldehyde resin combination can be improved by the addition of a modifier, preferably of a phenolic nature.
- Modifiers such as low molecular weight phenolic compounds, phenol, or low molecular weight ALCELL ® lignin can be used.
- Other modifiers which can be used include tris-(p- hydroxyphenyl) ethane (THPE), p-tert-butyl-phenol (PTBP), bisphenol-A (BPA), p-cresol, p-ethylphenol, p-sec- butylphenol, p-amylphenol, p-nonylphenol, p-dodecylphenol, 2,4-dimethylphenol, 2,4,6,-trimethylphenol, para-alkyl phenols with side chains of 18 to 24 and 24 to 28 carbons, polyhydroxystyrene, creosote blends and furfural which comprises washed furfural recovered in the process described in U.S. Patent application Ser. No. 07/649,683 filed February 1, 1991 and incorporated herein by reference.
- the modifier can be directly added to the powder phenol-formaldehyde resin and the dry organosolv lignin.
- a modifier such as phenol, p-tert-butylphenol (PTBP) and bisphenol-A (BPA) can be added in a modifier to organosolv lignin weight ratio of from about 0.5:99.5 to about 20:80, preferably 1:99 to 10:90.
- the combination of organosolv lignin and modifier can substitute for from about 15 to about 75% of the phenolic resin solids.
- Low molecular weight ALCELL ® lignin can also be added to the organosolv lignin as a modifier in a weight ratio of from about 5:95 to about 70:30, preferably 20:80 to 50:50.
- Low molecular weight ALCELL ® lignin is recovered as a tarry precipitate in the process described in U.S. Patent Application serial No. 07/649,683 filed February 1, 1991.
- Low molecular weight ALCELL ® lignin can be characterized by a low number average molecular weight in the range of less than 500 g/mole and a low glass transition temperature in the range of from about 24° to about 80°C.
- the low molecular weight ALCELL ® lignin is predominantly of the syringyl type, since by nitrobenzene oxidation, it yields a syringaldehyde to vanillin molar ratio of from about 2.7:1 to about 5.3:1.
- the low molecular weight ALCELL ® lignin can be dried first then can be added to the organosolv lignin or alternatively, the low molecular weight ALCELL ® lignin and the organosolv lignin can be mixed first then dried simultaneously prior to use.
- the dry organosolv lignin in waferboard and oriented strandboard manufacture, can be directly added to a liquid phenol- formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of dry organosolv lignin and dry solids in the phenolic resin.
- the phenol- formaldehyde resin can be prepared by condensation of formaldehyde and phenol in a mole ratio of from about 2 to about 3.0, preferably 2.2 to 2.5.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.12 to about 0.47, preferably 0.15 to 0.3 moles of alkali per mole of phenol.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- the organosolv lignin and phenol-formaldehyde resin can be sequentially used to cover the wafers covered with about 1% by weight (based on solids of a wax emulsion) in a weight ratio of from about 2 to about 5% (resin solids to dry wafers).
- the organosolv lignin in waferboard and oriented strandboard manufacture, can be copolymerized during the condensation reaction of phenol and formaldehyde and can replace from about 0.5 to about 40%, preferably from about 5 to about 30% of the phenolic resin solids in the resulting adhesive.
- the phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2 to about 4.5, preferably from about 2.2 to about 4.2 moles of formaldehyde per mole of phenol.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol.
- the organosolv lignin can be added in an amount sufficient to constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- the lignin/phenol- formaldehyde resin mixture can be blended with the wafers covered with about 1% by weight (based on solids of a wax emulsion) in a weight ratio of from about 2 to about 5% (resin solids to dry wafers).
- the organosolv lignin can be used as a partial replacement of phenol-formaldehyde resin used in plywood adhesive formulation.
- the phenol-formaldehyde resin can be prepared with a formaldehyde to phenol ratio of from about 2.3 to about 3.0, preferably from about 2.4 to about 2.6.
- the polymerization can be carried out under alkaline conditions in one or more alkali additions and preferably using sodium or potassium hydroxide, with a mole ratio of from about 0.5 to about 0.8, preferably of from about 0.65 to about 0.75 moles of alkali per mole of phenol.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- the organosolv lignin can be added to the resin during adhesive preparation and replace from about 2 to about 30%, preferably from about 15 to about 20% of the phenolic resin solids.
- the organosolv lignin in plywood adhesive formulation, can be copolymerized during resin manufacture and replace from about 0.8 to about 35%, preferably from about 4 to about 20% of the phenolic resin solids in the resulting adhesive.
- the phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2.4 to about 3.5, preferably from about 2.8 to about 3.1.
- the polymerization can be carried out under alkaline conditions, preferably using sodium or potassium hydroxide in one or more alkali additions with a mole ratio of from about 0.4 to about 1, preferably of from about 0.65 to about 0.85 moles of alkali per mole of phenol.
- the organosolv lignin can be added in a weight ratio with phenol of from about 2 to about 45%, preferably of from about 10 to about 30%.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- the resulting resin can be used during adhesive preparation.
- low molecular weight organosolv lignin such as ALCELL ® lignin can be used as a partial replacement for phenol in the manufacture of a phenol-formaldehyde resin for waferboard and oriented strandboard applications.
- the low molecular weight organosolv lignin can be copolymerized during the condensation reaction of phenol and formaldehyde and replace from about 0.5 to about 40%, preferably from about 5 to about 30% of the phenolic resin solids in the resulting adhesive.
- the phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2 to about 4.5, preferably from about 2.2 to about 4.2 moles of formaldehyde per mole of phenol.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol.
- the low molecular organosolv lignin can be added in an amount sufficient to constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- an alkaline solution of organosolv lignin can be added as a partial replacement for phenol during the synthesis of a phenol- formaldehyde resin for waferboard and oriented strandboard applications.
- An alkaline solution of organosolv lignin can be prepared using the organosolv lignin cake prior to drying or the organosolv lignin powder after drying recovered from the pulping processes described herein.
- An alkaline solution can also be prepared using the low molecular weight ALCELL ® lignin.
- alkali for example sodium or potassium hydroxide can be added in one or more additions in an amount of from about 10 to about 25%, preferably from about 12 to about 22% on a lignin weight basis.
- the organosolv lignin can be added slowly with agitation.
- the resulting organosolv lignin alkaline solution can be added to a liquid phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of dry organosolv lignin and dry solids in the phenolic resin.
- the phenol-formaldehyde resin can be prepared by condensation of formaldehyde and phenol in a mole ratio of from about 2 to about 3.0, preferably from about 2.2 to about 2.5.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.12 to about 0.47, preferably from about 0.15 to about 0.3 moles of alkali per mole of phenol.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- the alkaline organosolv lignin solution can be added to a phenol- formaldehyde resin for plywood applications.
- the organosolv lignin alkaline solution can be added to a phenol-formaldehyde resin during adhesive preparation and replace from about 2 to about 30%, preferably from about 15 to about 20% of the phenolic resin solids in the resulting adhesive.
- the phenol-formaldehyde resin can be prepared with a formaldehyde to phenol ratio of from about 2.3 to about 3.0, preferably from about 2.4 to about 2.6.
- the polymerization can be carried out under alkaline conditions in one or more alkali additions and preferably using sodium or potassium hydroxide, with a mole ratio of from about 0.5 to about 0.8, preferably of from about 0.65 to about 0.75 moles of alkali per mole of phenol.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- an organosolv lignin dispersion can be prepared and can be blended with a phenol-formaldehyde liquid resin for waferboard and oriented strandboard applications.
- Surfactants such as sodium and ammonium polymethacrylate, alkaline compounds such as sodium and ammonium hydroxide or other compounds which have a dispersant effect on the organosolv lignin can be used as a dispersing agent.
- the organosolv lignin cake prior to drying or the organosolv lignin powder after drying recovered from the pulping processes referred to herein can be used.
- low molecular weight ALCELL ® lignin can also be used.
- the dispersing agent can be added to water and the organosolv lignin can be added slowly with agitation and the level of dispersing agent and organosolv lignin adjusted so that the dispersion behaves thixotropically.
- the solids content of the dispersion are in the range of from about 45 to about 65%, preferably in the range of from about 50 to about 55%.
- the weight ratio of dispersing agent to organosolv lignin can be from about 0.5:99.5 to about 2:98, preferably from about 1:99 to about 1.5:98.5.
- the organosolv lignin dispersion can be directly added to a liquid phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of dry organosolv lignin and dry solids in the phenolic resin.
- the phenol-formaldehyde resin can be prepared by condensation of formaldehyde and phenol in a mole ratio of from about 2 to about 3.0, preferably from about 2.2 to about 2.5.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.12 to about 0.47, preferably from about 0.15 to about 0.3 moles of alkali per mole of phenol.
- Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- phenolation of organosolv lignin can be used in the manufacture of a phenol-formaldehyde resin for waferboard and oriented strandboard applications.
- Phenolation of organosolv lignin can be achieved by reacting organosolv lignin from about 10 to about 80%, preferably of from about 30 to about 60% of total reaction weight with phenol of from about 10 to about 80%, preferably of from about 20 to about 60% of total reaction weight under alkaline conditions, using sodium or potassium hydroxide in one or more alkali additions of from about 1 to about 20%, preferably from about 5 to about 10% of total reaction weight at a temperature of from about 80° to about 200°C, preferably of from about 110° to about 180° C and for from about 0.5 to about 2 hours, preferably from about 0.5 to about 1.5 hours.
- the phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2 to about 4.5, preferably of from 2.2 to about 4.2 moles formaldehyde per mole of phenol.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.1 to about 0.8, preferably of from about 0.2 to about 0.75 moles of alkali per mole of phenol.
- the phenolated organosolv lignin can constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Enough water can be added such that the total solids in the resin are about 57%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- phenolation of organosolv lignin can be used in the manufacture of a phenol-formaldehyde resin for plywood applications.
- •Phenolation of organosolv lignin can be achieved by reacting organosolv lignin of from about 10 to about 80%, preferably of from about 30 to about 60% of total reaction weight with phenol of from about 10 to about 80%, preferably of from about 20 to about 60% of total reaction weight under alkaline conditions, using sodium or potassium hydroxide of from about 1 to about 20%, preferably from about 5 to about 10% of total reaction weight at a temperature of from about 80 to about 200°C, preferably of from about 110° to about 180° C and for about 0.5 to about 2 hours, preferably from about 0.5 to about 1.5 hours.
- the phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2.4 to about 3.5, preferably of from 2.8 to about 3.1 per mole of phenol.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.4 to about 1, preferably from about 0.65 to about 0.85 moles of alkali per mole of phenol.
- the phenolated organosolv lignin can constitute from about 1 to about 45%, preferably from about 10 to about 30% on a phenol weight basis. Enough water can be added such that the total solids in the resin are about 42%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- organosolv lignin in another embodiment, can be methylolated by acid catalysis and the methylolated organosolv lignin can be used in the manufacture of adhesives for waferboards and oriented strandboard applications. Methylolation can be incorporated as a first step during the manufacture of the phenol-formaldehyde liquid resin. To promote solubility under acidic conditions, the organosolv lignin can be solubilized using a solvent which can be used in phenol-formaldehyde resin manufacture. A solvent such as trioxane, phenol or other phenolic compounds can be used.
- Organosolv lignin of from about 2 to about 60%, preferably from about 20 to about 40% of total reaction weight is dissolved in phenol of from about 20 to about 50%, preferably of from about 30 to about 45% of total reaction weight.
- Formaldehyde of from about 5 to about 50%, preferably of from about 10 to about 30% of total reaction weight is added under acidic conditions using a mineral or organic acid, preferably using sulfuric acid of from about 0.01 to about 3%, preferably of from about 0.1 to about 2% of total reaction weight.
- the mixture is heated to from about 40 to about 100°C, preferably to from about 60 to about 90°C for about 30 to about 180 minutes, preferably for about 60 to about 120 minutes.
- the phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is fro about 2 to about 4.5, preferably of from 2.2 to about 4.2 moles formaldehyde per mole of phenol.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol.
- the organosolv lignin can constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Enough water can be added such that the total solids in the resin are about 57%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- Organosolv lignin of from about 2 to about 60%, preferably from about 20 to about 40% of total reaction weight is dissolved in phenol of from about 20 to about 50%, preferably of from about 30 to about 45% of total reaction weight.
- the mixture is heated to from about 40 to about 100°C, preferably to from about 60 to about 90°C for about 30 to about 180 minutes, preferably for about 60 to about 120 minutes.
- the phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2.4 to about 3.5, preferably of from 2 to about 3.1 moles formaldehyde per mole of phenol.
- the polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.4 to about 1, preferably from about 0.65 to about 0.85 moles of alkali per mole of phenol.
- the organosolv lignin can constitute from about 1 to about 45%, preferably from about 10 to about 30% on a phenol weight basis. Enough water can be added such that the total solids in resin are about 42%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.
- the wood composites of the invention are manufactured using standard manufacturing procedures and techniques except where specifically noted.
- Tables 1, 2, 3, 4 and 5 illustrate the parameters used in the manufacture of the wood composites of the invention including novel adhesive formulation techniques and methods, as more particularly set forth in the following examples.
- Table 6 shows the physical properties of boards made by substituting about 20% of a particular powder phenol-formaldehyde resin BAKELITE 9111 (manufactured by Bakelite Thermosets Limited, Belleview, Ontario, Canada) blended with different dry lignins.
- the boards were manufactured according to the parameters in Table 1.
- the results in Table 6 indicate that organosolv lignin such as ALCELL ® lignin was the best substitute in terms of improving board properties.
- a powder phenol- formaldehyde resin e.g. BD909
- an ALCELL ® lignin and a modifier such as phenol.
- About nine parts of dry ALCELL ® lignin in about ten parts of water was mixed with about one part of phenol.
- the mixture was air dried into a powder then used to substitute for about 50% of a phenol-formaldehyde resin.
- Waferboards were manufactured according to the parameters in Table 1.
- Table 8 indicate that the performance of the combination of dry ALCELL ® lignin and a phenol- formaldehyde resin was improved by a modifier such as phenol and superior board properties were obtained.
- a modifier such as low molecular weight ALCELL ® lignin can be used to improve the performance of organosolv lignin such ALCELL ® lignin with for example a phenol-formaldehyde resin such as BD909 as shown in Table 10.
- the tarry low molecular weight ALCELL® lignin was added to the ALCELL ® lignin in the proportions shown in Table 10, and the mixture was heated to about 120°C. The mixture was cooled to about 25°C and ground into a powder. The powder was blended with a phenol- formaldehyde resin such as BD909. The waferboards were manufactured using the parameters in Table 1.
- a powder phenol- formaldehyde resin e.g. BD909
- an ALCELL ® lignin and a modifier such as tris-(p- hydroxyphenyl) ethane (THPE), bisphenol-A (BPA), p-tert- butylphenol (PTBP), p-cresol, p-nonylphenol, para-alkyl phenol with a side chain of 18 to 24 carbons, 2,4- dimethylphenol and 2,4,6-trimethylphenol.
- THPE tris-(p- hydroxyphenyl) ethane
- BPA bisphenol-A
- PTBP p-tert- butylphenol
- p-cresol p-nonylphenol
- para-alkyl phenol para-alkyl phenol with a side chain of 18 to 24 carbons
- 2,4- dimethylphenol and 2,4,6-trimethylphenol about nine parts of dry ALCELL ® lignin in about ten parts of water were
- a powder phenol- formaldehyde resin e.g. GP5479
- an ALCELL ® lignin and a modifier such as p-tert-butylphenol (PTBP).
- PTBP p-tert-butylphenol
- a dry blend of the modifier was prepared by grinding the modifier to a particle size close to the particle size of ALCELL ® lignin.
- the dry ALCELL ® lignin and the modifier were combined into dry blends containing about 1, about 4 and about 10% of the modifier on a total blend weight basis.
- Waferboards were manufactured according to the parameters in Table 4. The results in Table 13 indicate that the phenolic modifiers effectively increase the compatibility of the ALCELL ® lignin and superior board properties were obtained.
- Table 14 indicate that the performance of the combination of a dry organosolv lignin such as ALCELL ® lignin blended with a powder phenol- formaldehyde resin such as BD909 can be improved by increasing the press time to about 200 seconds or longer at a press temperature of about 400°F. Results in Table 14 how improved board properties.
- the waferboards were manufactured according to the parameters in Table 3.
- This example illustrates the procedure followed in the preparation of a liquid phenolic resin used to formulate a liquid adhesive for waferboard applications.
- Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below.
- the final resin composition was about 57% total solids and the viscosity was about 200 cps (measured at 25 ⁇ C).
- the organosolv lignin was directly added to the condensation reaction mixture of phenol and formaldehyde and copolymerized during such reaction. Subsequently, this resin was used to formulate a liquid adhesive for waferboard applications. About 2.7 moles of formaldehyde, about 0.05 moles sodium hydroxide and about 20% ALCELL ® lignin on a weight basis with phenol were reacted for about 90 minutes at a temperature of about 70°C. The reaction mixture was cooled to about 30°C, and about one mole of phenol and about 0.2 moles of sodium hydroxide were added.
- the mixture was then heated to about 80°C and polymerization was continued until a target viscosity of from about 200 to about 700 cps (measured at 25°C) was reached.
- Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below.
- the lignin/phenolic resin composition was about 57% total solids of which about 12% was organosolv lignin.
- wood wafers e.g. Aspen
- a wax emulsion e.g. PARACOL 802N manufactured by Hercules, Wilmington, DE
- Organosolv lignin such ALCELL ® lignin in dry form and the liquid phenol-formaldehyde resin of Example 12 were used to cover the wafers in a weight ratio of about 20:80, the organosolv lignin was used to cover the wafers prior to spraying with liquid phenol-formaldehyde resin.
- the total phenol-formaldehyde resin and organosolv lignin solids were blended on the wafers at about 4.5% (w/w).
- Example 14 The mixture of wafers of Example 14 containing about 3.6% Example 12 liquid phenol-formaldehyde resin and about 0.9% dry ALCELL ® lignin were pressed into 3/8" boards at a temperature of about 410°F, at a pressure of about 540 psig and for about 5 minutes and according to the manufacturing parameters of Table 2. These waferboards were compared to control boards manufactured with about 4.5% Example 12 liquid phenol-formaldehyde resin and no ALCELL ® lignin.
- Example 14 two batches of wood wafers were made according to the procedure of Example 14 without the addition of dry ALCELL ® lignin.
- the wafers in each batch contain about 4.5% of Example 13 liquid phenol- formaldehyde resins at about 390 cps and at about 700 cps viscosity.
- the wafers were pressed into 3/8" boards at a temperature of about 410°F, at a pressure of about 540 psig and for about 5 minutes and according to the manufacturing parameters of Table 2. These waferboards were compared to control boards manufactured with about 4.5% Example 12 liquid phenol-formaldehyde resin and no ALCELL ® lignin.
- This example illustrates the procedure followed in the preparation of a liquid phenol-formaldehyde resin for plywood applications.
- the organosolv lignin was added to the liquid phenol-formaldehyde resin during plywood adhesive formulation (see Example 20).
- About one mole of phenol, about 2.45 moles of formaldehyde, the water and a first portion of the sodium hydroxide, preferably about 0.15 moles sodium hydroxide per mole of phenol were reacted at a temperature of from about 80° to 100°C until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached.
- a second portion of the sodium hydroxide preferably about 0.2 moles were added and the polymerization was carried forward at a temperature of from about 65° to 75°C, and until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached.
- a third portion of sodium hydroxide preferably 0.15 moles were added and the reaction was continued at a temperature of from about 65° to 75°C until a viscosity of from about 1500 to 1800 cps (measured at 25°C) was reached.
- Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below.
- the final resin composition was about 42% total solids and the resin viscosity was about 800 cps (measured at 25°C).
- the organosolv lignin was directly added to the condensation reaction mixture of phenol and formaldehyde and copolymerized during such reaction.
- the lignin-containing phenol-formaldehyde resin can be used to formulate an adhesive for plywood applications (see Example 19).
- the mixture was cooled to a temperature of about 30°C and one mole of phenol, about 0.17 moles sodium hydroxide and about 2.52 moles of formaldehyde and the remaining water were added and the polymerization was continued until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached.
- the mixture was cooled to a temperature of from about 55° to 75°C, about 0.23 moles of sodium hydroxide were added and the polymerization was continued until a viscosity of from about 2000 to 2500 cps.
- About 0.17 moles of sodium hydroxide were added and the polymerization was continued until a viscosity of from about 1700 to 2000 cps (measured at 25°C) was reached.
- Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below.
- the lignin/phenolic resin composition was about 42% total solids and the resin viscosity was about 1000 cps (measured at 25°C).
- An adhesive for plywood manufacture can be prepared in a variety of ways and different techniques have been employed to formulate the adhesive depending on the application.
- the balance of Example 18 resin, about 56.93% by weight was added to the mixture.
- the final adhesive composition was from about 24 to 32% total solids of which about 1 to 7% was organosolv lignin.
- the final adhesive viscosity was about 5600 cps (measured at 25°C).
- An adhesive for plywood manufacture was prepared using the procedure of Example 19.
- about 13.62% by weight of Example 17 phenol-formaldehyde resin, about 18.54% by weight water, about 11.17% by weight of a mixture of additives (e.g. fillers or viscosity modifiers), about 3.07% by weight alkali, preferably sodium hydroxide, and about 4.78% organosolv lignin, preferably ALCELL ® lignin were mixed for from about 5 to 15 minutes.
- the balance of Example 17 resin, about 48.81% by weight was added to the mixture.
- the final adhesive composition was from about 24 to 32% resin solids of which about 2 to 10% was organosolv lignin.
- the final adhesive viscosity was about 3780 cps (measured at 25°C).
- organosolv lignin was added to a commercial adhesive (e.g. Borden 3130H) .
- a commercial adhesive e.g. Borden 3130H
- About 13.60% of a commercial resin e.g. Borden 3130
- about 18.53% water about 11.2% of a mixture of additives (e.g. fillers or viscosity modifiers), about 4.8% organosolv lignin, preferably ALCELL ® lignin and about 3.06% alkali, preferably sodium hydroxide were mixed for from about 5 to 15 minutes.
- the balance of the commercial resin, about 48.8% by weight was added to the mixture.
- the final adhesive composition was about 26.85% resin and about 4.7% organosolv lignin.
- the final adhesive viscosity was about 7200 cps (measured at 25°C) .
- the following examples are illustrative of a testing procedure which compares the adhesion performance of the lignin-containing plywood adhesive of the invention with a commercial adhesive.
- the adhesives as prepared were particularly suited for use with Douglas Fir plywood and can be modified for other applications (e.g. by spray or mechanical spreader) and for use with other veneers (e.g. southern pine) .
- Test panels were prepared under extreme manufacturing conditions in order to accentuate the two major causes of panel failure, namely over-penetration and dry-out. Shear specimens were prepared and tested for over-penetration and dry-out according to an approved procedure (e.g. American Plywood Association, PS 1-83).
- Example 19 An adhesive for plywood manufacture was prepared using the procedure of Example 19.
- the plywood adhesive was suitable for commercial applications.
- about 13.62% by weight of Example 17 phenol-formaldehyde resin, about 19.11% by weight water, about 10.62% by weight of a mixture of additives (e.g. fillers or viscosity modifiers), about 3.11% by weight alkali, preferably sodium hydroxide, and about 4.82% organosolv lignin, preferably ALCELL ® lignin were mixed for from about 5 to 15 minutes.
- the balance of Example 17 resin, about 48.90% by weight was added to the mixture.
- the final adhesive composition was about 26.6% total solids of which about 4.82% was organosolv lignin.
- the final adhesive viscosity was about 7000 cps (measured at 25°C).
- the adhesives in Table 20 were tested by the preparation of three ply panels made with 1/8" Douglas Fir veneer. The panels were pressed using a press temperature of about 300°F and a pressure of about 200 psi. To accentuate over-penetration, a wet glue spread of about 70 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of from about 2 to 3 minutes and a pressing time of about 6 minutes. To accentuate dry-out, a wet glue spread of about 40 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of about 40 minutes and a pressing time of about 5 minutes. The press was closed immediately after loading so that there was no "fry-time". The panels were tested using the vacuum pressure and four- hour alternate boil test and the results are summarized in Table 20. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- Example 25 Three ply panels were prepared and tested as in Example 23. Results in Table 21 indicate that the adhesive of Example 20 performs better than commercial adhesives with or without lignin. EXAMPLE 25
- the adhesives in Table 22 were tested by the preparation of 13/16" five ply panels made with Douglas Fir veneer.
- the panels were pressed for varying press times, at a press temperature of about 300°F, and a pressure of about 200 psi.
- the wet glue spread was about 60 lbs of adhesive per 1,000 square feet of double glue line were used with an assembly time of about 15 minutes.
- the "fry-time" was about 0.5 minutes.
- the panels were tested using the vacuum pressure and four- hour alternate boil test and the results were summarized in Table 20. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- Example 22 The adhesive of Example 22 was tested in a commercial mill trial by the preparation of 5/6" three ply, 21/32" five ply and 25/32" five ply panels made with
- Douglas Fir veneer The panels were cold pressed at a pressure of about 150 psi and for about 5 minutes, and hot pressed using a press temperature of about 275°F, a pressure of about 200 psi and for about 5.5 minutes. A wet glue spread of about 65 lbs of adhesive per 1,000 square feet of double glue line was used. The press was closed immediately after loading. The panels were tested using the vacuum pressure and four-hour alternate boil tests and the results were summarized in Table 23. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 23 indicate that Example 22 adhesive has excellent board properties.
- ALCELL ® lignin dispersions were prepared and were blended with a phenol-formaldehyde resin to form the adhesive.
- about 1.2% ammonium hydroxide (ammonia basis) was used. Ammonium hydroxide was added to water and then ALCELL® lignin was added slowly with agitation to from a stable dispersion. The lignin dispersion contained about 51.3% total solids.
- An adhesive for waferboard manufacture was prepared with the dispersion of Example 27.
- About 58.6 grams of the lignin dispersion of Example 27 was mixed with 214.4 grams of a phenol-formaldehyde resin (e.g. face resin PH-102) and 4.9 grams of water.
- the final adhesive composition was about 54% total solids of which about 20% was organosolv lignin.
- the final adhesive viscosity was about 379 cps (measured at 25°C).
- the final adhesive composition was adjusted by addition of water to about 50% total solids.
- the final adhesive viscosity was about 222 cps (measured at 25°C).
- Example 28 The adhesive of Example 28 was tested by the preparation of boards manufactured according to the parameters of Table 5. The results of board testing were shown in Table 24 and demonstrate that the boards prepared were competitive with control boards.
- Example 27 replaces about 20% of the phenol used during the synthesis of a phenol-formaldehyde resin.
- the procedure of Example 13 was followed where the lignin dispersion of Example 27 was used instead of the organosolv lignin.
- the final resin composition was about 54% solids of which about 12% was organosolv lignin.
- the final adhesive viscosity was about 174 cps (measured at 25°C).
- alkaline ALCELL ® lignin solution was prepared by addition of sodium hydroxide and ALCELL ® lignin to water.
- About 1200 grams of a lignin cake containing about 65% solids were mixed with about 270 grams of an about 50% sodium hydroxide solution and about 559 grams of water to obtain a solution containing about 44.9% solids and having a viscosity of about 1300 cps
- the solution composition was adjusted by addition of water to contain about 40% solids and to a viscosity of about 227 cps (measured at 25°C) .
- the alkaline ALCELL ® lignin solution of Example 32 can be used as a partial replacement for phenol during phenol-formaldehyde resin synthesis.
- the procedure of Example 13 was followed and the alkaline organosolv lignin solution of Example 32 replaces the organosolv lignin used.
- the final adhesive composition was about 54% total solids of which about 12% was organosolv lignin.
- the final adhesive viscosity was about 204 cps (measured at 25°C).
- the alkaline lignin solution of Example 32 was added to the phenol-formaldehyde resin of Example 17 and used in plywood applications.
- about 568.7 grams of Example 17 phenol- formaldehyde resin was blended with 128.5 grams of the alkaline lignin solution of Example 32.
- the final adhesive was about 42.4% total solids of which about 15% was organosolv lignin.
- the final adhesive a viscosity was about 685 cps (measured at 25°C) .
- Example 35 The adhesive of Example 35 was tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. In this example, the panels were pressed for about 6 minutes, at a press temperature of about 300°F and a pressure of about 200 psi. The panels were tested using the vacuum pressure and four-hour alternate boil test under conditions that promote over- penetration. The adhesive was compared to a commercial phenol-formaldehyde resin. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 27 indicate that the adhesive of Example 35 was performing equal to or better than the commercial adhesive. EXAMPLE 37
- Example 35 was tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. In this example, the panels were pressed for about 5 minutes, at a press temperature of about 300°F, and a pressure of about 200 psi. The panels were tested using the vacuum pressure and four-hour alternate boil test under conditions that promote dry-out. The adhesive was compared to a commercial phenol- formaldehyde resin. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 28 indicate that the adhesive of Example 35 was performing equal to or better than the commercial adhesive.
- Example 35 was tested by the preparation of 5/8" three ply panels made with 1/8" Douglas Fir veneer.
- standard production methods were simulated by using about 6.5 minutes prepress time, about one minute closed assembly time, about 0.5 minutes fry time at an assembly time ranging from about 5 to 45 minutes.
- the panels were pressed for about 6.5 minutes, at a press temperature of about 300°F and at a pressure of about 200 psi.
- the panels were tested under normal conditions.
- the adhesive was compared to a commercial phenol-formaldehyde resin. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- the results in Table 29 indicate that the adhesive of Example 35 was performing equal to or better than the commercial adhesive.
- ALCELL ® lignin was phenolated 5 prior to phenol-formaldehyde resin synthesis for waferboards and oriented strandboard applications. About 0.67 moles phenol, about 0.14 moles sodium hydroxide and about 20% organosolv lignin on phenol weight basis were reacted for about 60 minutes and at a temperature of about
- reaction mixture was cooled to about 45°C, and about 0.33 moles phenol, about 4.1 moles formaldehyde and about 0.24 moles sodium hydroxide were added. Enough water was added such that the final adhesive has a total resin solids content of about 55%. The mixture was heated
- composition was about 55% resin solids of which about 12% was organosolv lignin.
- the final adhesive viscosity was about 205 cps (measured at 25°C) .
- Example 39 The adhesive of Example 39 was tested by the 25 preparation of three layers waferboard panels. The manufacturing conditions of Table 5 were followed. The results of board testing were shown in Table 30 and demonstrate that the boards prepared were competitive with control boards. EXAMPLE 41
- ALCELL ⁇ lignin was phenolated prior to phenol-formaldehyde resin synthesis used in plywood applications.
- about 15% of the total phenol used in the resin was replaced by organosolv lignin such as ALCELL ® lignin.
- organosolv lignin such as ALCELL ® lignin.
- About 0.28 moles of phenol and about 0.06 moles sodium hydroxide were reacted for about 60 minutes and at a temperature of about 180°C.
- the mixture was cooled to about 45° and about 0.72 moles phenol, about 2.69 moles formaldehyde and water was added in an amount sufficient such that the final resin solids were about 42% solids.
- About 0.12 moles of sodium hydroxide were added and the mixture was refluxed for about 20 minutes.
- the mixture was then cooled to about 80°C and the polymerization continued until a viscosity of about 2500 cps (measured at 25°C) was reached.
- the mixture was then cooled to about 70°C and about 0.24 moles sodium hydroxide was added.
- the polymerization was continued until a viscosity of about 2500 cps (measured at 25°C) was reached.
- the mixture was cooled to about 65°C and about 0.18 moles sodium hydroxide were added.
- the polymerization was continued until a viscosity of from about 1500 cps (measured at 25°C) was reached.
- Urea was added in an amount sufficient to constitute about 5% of the resin weight and the resin was cooled to 25°C or below.
- the final adhesive composition was about 42% total solids of which about 8% was organosolv lignin.
- An adhesive for plywood manufacture was prepared using the procedure of Example 19.
- Example 41 phenol- formaldehyde resin, about 21.35% by weight water, about 12.09% by weight of a mixture of additives (e.g. fillers or viscosity modifiers) and about 2.49% by weight alkali, preferably sodium hydroxide, were mixed for from about 5 to 15 minutes.
- the balance of Example 41 resin, about 56.93% by weight was added to the mixture.
- the final adhesive composition was from about 24 to 32% total solids of which about 1 to 7% was organosolv lignin.
- the final adhesive viscosity was about 5600 cps (measured at 25°C).
- the adhesives in Table 31 with varying levels of ALCELL® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer.
- the panels were pressed using a press temperature of about 300°F and a pressure of about 200 psi.
- a wet glue spread of about 70 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of from about 2 to 3 minutes and a pressing time of about 6 minutes.
- the press was closed immediately after loading so that there was no "fry-time”.
- the panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 31.
- a high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- the adhesives in Table 32 with varying levels of ALCELL ® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. To accentuate dry-out, a wet glue spread of about 40 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of about 40 minutes and a pressing time of about 5 minutes. The press was closed immediately after loading so that there was no "fry-time”. The panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 32. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- low molecular weight ALCELL ® lignin was used as a partial replacement for phenol in the manufacture of phenol-formaldehyde resins for waferboards and oriented strandboard application.
- the procedure of Example 13 was used and the low molecular weight ALCELL ® lignin replaces the organosolv lignin.
- the final adhesive composition was about 54% total solids of which about 12% was organosolv lignin.
- the final adhesive viscosity was about 204 cps (measured at 25°C) .
- Example 46 The adhesive of Example 46 was tested by the preparation of three layers waferboard panels. The manufacturing conditions of Table 5 were followed. The results of board testing are shown in Table 34 and demonstrate that the boards prepared were competitive with control boards.
- ALCELL ® lignin substituted for about 20% of the phenol on a phenol weight basis used in phenol-formaldehyde resin manufacture About 1.3 moles of formaldehyde, 0.06 moles of sodium hydroxide and about 20% ALCELL ® lignin on a weight basis with phenol were reacted for about 90 minutes and at a temperature of about 70°C.
- the reaction mixture was cooled to about 30°C, and about one mole of phenol, about 1.15 mole formaldehyde and about 0.27 moles of sodium hydroxide were added.
- the mixture was heated to about 80°C and polymerization was continued until a target viscosity of from about 200 to 700 cps (measured at 25°C) was reached.
- Urea was added in an amount sufficient to react with the excess formaldehyde and the resin was quickly cooled to about 25°C or below.
- the final resin composition was about 57% total solids of which about 12% was organosolv lignin.
- the final adhesive viscosity was about 240 cps (measured as 25°C).
- organosolv lignin such as
- ALCELL ® lignin substituted for about 40% phenol on a weight basis during phenol formaldehyde resin manufacture About 2.9 moles of formaldehyde, about 0.16 moles sodium hydroxide, about 40% organosolv lignin on a weight basis with phenol and water were reacted for about 90 minutes and at a temperature of about 70°C.
- the reaction mixture was cooled to about 45 ⁇ C, about one mole phenol and about 0.31 moles of sodium hydroxide were added.
- the mixture was heated to about 80°C and polymerization was continued until a target viscosity of about 200 to 400 cps (measured at 25°C) was reached.
- Urea was added in an amount equal to about 5% of total resin weight, and the resin was quickly cooled to about 25°C or below.
- the final resin composition was about 57% total solids of which about 25% was organosolv lignin.
- the resin viscosity was about 240 cps (measured at 25°C).
- ALCELL ® lignin was acid methylolated as a first step in the synthesis of a phenol- formaldehyde resin for waferboard and oriented strandboard applications. About 20% on a weight basis of the phenol used in the manufacture of the phenol-formaldehyde resin was replaced by organosolv lignin. Thus 18.8 grams of lignin were dissolved in about 0.32 moles of phenol, about 0.39 moles formaldehyde and 0.003 moles of sulfuric acid. The mixture was reacted for about 45 minutes at a temperature of about 80°C. The reaction mixture was cooled to about 45°C and about 0.006 moles sodium hydroxide was added to neutralize the sulfuric acid.
- Example 51 The adhesive of Example 51 was tested as a face resin in waferboard applications. Results in Table 36 demonstrate that the boards prepared were competitive with control boards.
- ALCELL ® lignin was acid methylolated as a first step in the synthesis of a phenol- formaldehyde resin for plywood applications. About 15% on a weight basis of the phenol used in the manufacture of the phenol-formaldehyde resin was replaced by ALCELL ® lignin. About 14.1 grams of organosolv lignin, about 0.23 moles phenol, about 0.31 moles formaldehyde and about 0.002 moles sulfuric acid were reacted for about 45 minutes at a temperature of about 80°C. The mixture was cooled to a temperature of about 35°C and about 0.012 moles sodium hydroxide was added to neutralize the sulfuric acid.
- Enough water was added such that the final resin solids were about 42%. About 0.77 moles phenol and about 2.84 moles formaldehyde were added. About 0.18 moles of sodium hydroxide were added. The mixture was heated to reflux for about 15 minutes then cooled to about 80°C. The polymerization was continued until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. The mixture was cooled to about 70°C. About 0.24 moles of sodium hydroxide were added and the polymerization continued until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. The mixture was cooled to about 65°C.
- An adhesive for plywood manufacture was prepared using the procedure of Example 19.
- Example 19 about 7.11% by weight of Example 52 phenol- formaldehyde resin, about 21.35% by weight water, about
- adhesive composition was from about 24 to 32% total solids of which about 1 to 7% was organosolv lignin.
- the final adhesive viscosity was about 5600 cps (measured at 25°C) .
- the adhesives in Table 37 with varying levels of 20 ALCELL ® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer.
- the panels were pressed using a press temperature of about 300°F and a pressure of about 200 psi.
- a wet glue spread of about 70 25 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of from about 2 to 3 minutes and a pressing time of about 6 minutes.
- the press was closed immediately after loading so that there was no "fry-time”.
- the panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 37.
- a high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- the adhesives in Table 38 with varying levels of ALCELL ® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. To accentuate dry-out, a wet glue spread of about 40 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of about 40 minutes and a pressing time of about 5 minutes. The press was closed immediately after loading so that there was no "fry-time”. The panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 38. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- ALCELL® lignin substitution were tested by the preparation of 5/8" five ply panels made with 1/8" Douglas Fir veneer.
- adhesion performance was studied under simulated normal assembly conditions at slightly high and normal wet spreads. Normal production methods were simulated by using 5 minutes prepress conditions, one minute closed assembly time and 0.5 minute fry time at different assembly times ranging from about 5 to 30 minutes.
- the press temperature was set at about 300°F, and a pressure of about 200 psi.
- the wet glue spread was about 60 lbs of adhesive per 1,000 square feet of double glue line.
- the panels were tested using the vacuum pres ⁇ sure and four-hour alternate boil test and the results were summarized in Table 39. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.
- Binder Content (% by wafer weight) 2.5 Wax Content (% solids by wafer weight) 1.0
- Binder Content (% by wafer weight) 4.5 Wax Content (% solids by wafer weight) 1.0
- Binder Content (% by wafer weight) 1.95
- Wax Content (% solids by wafer weight) 1.0
- Binder Content (% by wafer weight) 1.95 Wax Content (% solids by wafer weight) 1
- Wax Content (% solids by wafer weight) 0.9
- Figures in parenthesis are in percent (%) and based on values for board made with a 100% phenol- formaldehyde resin.
- BD023 and BD802 are both manufactured by Reichhold Ltd, Bellevue, Ontario, Canada.
- GP5415 is manufactured by Georgia Pacific, Crossett, Arkansas.
- Example 12 Resin 5138 116 279 (100) (100) (100)
- the wet glue spread is about 70 lbs of adhesive per 1,000 square feet of double glue line.
- the assembly time is about 2.5 minutes.
- the wet glue spread is about 40 lbs of adhesive per 1,000 square feet of double glue line.
- the assembly time is about 40 minutes.
- the wet glue spread is about 65 lbs of adhesive per 1,000 square feet of double glue line.
- the assembly time is about 5 to 45 minutes.
- the prepress time is about 6 minutes.
- the closed assembly time is about one minute.
- the dry organosolv lignin could be mixed into a low viscosity liquid phenolic resin for use in waferboard manufacture and alternatively, the organosolv lignin could be formulated as a component of a wax emulsion by mixing with small amounts of a dispersing agent.
- the performance of the plywood adhesive could also be improved by the addition of a modifier.
- the organosolv lignin and the phenolic resin could be applied simultaneously by independent application means.
- the lignin can be applied in liquid, slurry or powder form.
- the lignin in either liquid, slurry or powder form could be added to the liquid precursor of a powder phenol-formaldehyde resin and the mixture spray-dried and used to obtain a lignin/phenol formaldehyde resin blend.
Abstract
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US68256591A | 1991-04-09 | 1991-04-09 | |
US682565 | 1991-04-09 | ||
PCT/US1992/002963 WO1992018557A1 (en) | 1991-04-09 | 1992-04-09 | Improved lignin-based wood adhesives |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0646148A4 true EP0646148A4 (en) | 1994-06-27 |
EP0646148A1 EP0646148A1 (en) | 1995-04-05 |
Family
ID=24740239
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP92909872A Ceased EP0646148A1 (en) | 1991-04-09 | 1992-04-09 | Improved lignin-based wood adhesives |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP0646148A1 (en) |
JP (1) | JPH06506967A (en) |
AU (1) | AU1680792A (en) |
CA (1) | CA2108176A1 (en) |
FI (1) | FI934392A (en) |
NO (1) | NO933601L (en) |
WO (1) | WO1992018557A1 (en) |
Families Citing this family (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1993021260A2 (en) * | 1992-04-09 | 1993-10-28 | Alcell Technologies Inc. | Lignin in wood composites |
DE4331656C2 (en) * | 1993-03-12 | 1999-01-14 | Bakelite Ag | Binder mixture |
CA2159711A1 (en) * | 1993-04-09 | 1994-10-27 | Albert W. Creamer | Lignin-based formulations for wood composites |
DE69828342T2 (en) * | 1997-02-27 | 2005-12-08 | Borden Chemical Inc., Columbus | WOOD COMPOSITE MATERIALS |
JP2005060590A (en) * | 2003-08-18 | 2005-03-10 | Sekisui Chem Co Ltd | Adhesive, woody composite material, method for producing woody composite material, and method for peeling adhesive |
CN101857787B (en) * | 2010-06-13 | 2011-07-27 | 北京林业大学 | Method for preparing bio-oil-phenolic resin modified starch adhesive |
CN103201395B (en) | 2010-06-26 | 2016-03-02 | 威尔迪亚有限公司 | Sugar mixture and production thereof and using method |
IL206678A0 (en) | 2010-06-28 | 2010-12-30 | Hcl Cleantech Ltd | A method for the production of fermentable sugars |
CN102134305B (en) * | 2011-02-16 | 2012-07-25 | 福州大学 | Solvent lignin-modified epoxy resin curing agent and preparation method thereof |
GB2524906B8 (en) | 2011-04-07 | 2016-12-07 | Virdia Ltd | Lignocellulose conversion processes and products |
FI124944B (en) * | 2011-04-08 | 2015-03-31 | Upm Kymmene Corp | A method of making a binder composition, a binder composition, an adhesive composition, a layered composite structure, and uses of the binder composition and the adhesive composition |
US9163169B2 (en) | 2012-03-13 | 2015-10-20 | Georgia-Pacific Chemicals Llc | Adhesive compositions having a reduced cure time and methods for making and using same |
FI123934B (en) | 2012-03-29 | 2013-12-31 | Upm Kymmene Corp | Use of low molecular weight lignin for the preparation of a binder composition |
US9458298B2 (en) | 2012-10-01 | 2016-10-04 | Georgia-Pacific Chemicals Llc | Methods for making lignocellulose containing composite products |
US9586338B2 (en) | 2012-10-01 | 2017-03-07 | Georgia-Pacific Chemicals Llc | Methods for making lignocellulose containing composite products |
US9243114B2 (en) | 2013-03-14 | 2016-01-26 | Georgia-Pacific Chemicals Llc | Binder compositions and methods for making and using same |
US9587077B2 (en) | 2013-03-14 | 2017-03-07 | Georgia-Pacific Chemicals Llc | Methods for making composite products containing lignocellulose substrates |
FI126736B (en) | 2013-11-26 | 2017-04-28 | Upm Kymmene Corp | Process for treating lignin and preparing a binder composition |
CA2934689C (en) | 2013-12-20 | 2020-03-10 | Georgia Pacific Chemicals Llc | Release aids with adjustable cloud points for creping processes |
WO2015116612A1 (en) * | 2014-01-28 | 2015-08-06 | Georgia-Pacific Chemicals Llc | Lignin adhesive |
US9587115B2 (en) | 2014-04-02 | 2017-03-07 | Georgia-Pacific Chemicals Llc | Methods for making lignocellulose composite products |
EP3126401A4 (en) | 2014-04-02 | 2017-02-15 | Georgia-Pacific Chemicals LLC | Methods for making lignocellulose composite products with oxidative binders and complexed metal catalyst |
WO2015153520A1 (en) | 2014-04-02 | 2015-10-08 | Georgia-Pacific Chemicals Llc | Methods for making lignocellulose composite products with oxidative binders and encapsulated catalyst |
US20160096985A1 (en) * | 2014-10-07 | 2016-04-07 | Georgia-Pacific Chemicals Llc | Adhesives containing a resin, a kraft lignin, and a surfactant and methods for making and using same |
ES2734983T3 (en) | 2014-12-04 | 2019-12-13 | Ball Beverage Packaging Europe Ltd | Printing apparatus |
CA2979990C (en) | 2015-04-02 | 2023-03-28 | Stora Enso Oyj | An activated lignin composition, a method for the manufacturing thereof and use thereof |
US10549921B2 (en) | 2016-05-19 | 2020-02-04 | Rexam Beverage Can Company | Beverage container body decorator inspection apparatus |
WO2018047772A1 (en) * | 2016-09-09 | 2018-03-15 | 出光興産株式会社 | Method for producing lignin-containing resin composition and lignin-containing resin molded article |
SE543465C2 (en) * | 2018-04-20 | 2021-02-23 | Stora Enso Oyj | Process for preparing a bonding resin |
CA3091213A1 (en) | 2019-08-26 | 2021-02-26 | Walker Industries Holdings Limited | Aqueous wax emulsions and dispersions and uses thereof |
CN112778963B (en) * | 2021-02-09 | 2023-03-17 | 河南银金达新材料股份有限公司 | Transparent adhesive for PETG (polyethylene terephthalate glycol) film and preparation method thereof |
CN114456759B (en) * | 2022-01-26 | 2023-07-18 | 山东大唐宅配家居有限公司 | High-strength environment-friendly multilayer composite board and preparation method thereof |
FI20225456A1 (en) * | 2022-05-25 | 2023-11-26 | Fortum Oyj | Method for preparing lignin-phenol-formaldehyde resins of controlled viscosity |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5010156A (en) * | 1988-05-23 | 1991-04-23 | Eastman Kodak Company | Organosolv lignin-modified phenolic resins and method for their preparation |
-
1992
- 1992-04-09 WO PCT/US1992/002963 patent/WO1992018557A1/en not_active Application Discontinuation
- 1992-04-09 AU AU16807/92A patent/AU1680792A/en not_active Abandoned
- 1992-04-09 EP EP92909872A patent/EP0646148A1/en not_active Ceased
- 1992-04-09 CA CA002108176A patent/CA2108176A1/en not_active Abandoned
- 1992-04-09 JP JP4509104A patent/JPH06506967A/en active Pending
-
1993
- 1993-10-06 FI FI934392A patent/FI934392A/en not_active Application Discontinuation
- 1993-10-08 NO NO933601A patent/NO933601L/en unknown
Non-Patent Citations (4)
Title |
---|
J. H. LORA ET AL.: "Characteristics and potential applications of lignin produced by an organosolv pulping process", ACS SYMPOSIUM SERIES, vol. 397, 1989, USA, pages 312 - 323 * |
PH. M. COOK ET AL.: "Organosolv lignin-modified phenolic resins", ACS SYMPOSIUM SERIES, vol. 397, 1989, USA, pages 324 - 333 * |
See also references of WO9218557A1 * |
W. LANGE ET AL.: "Einfluss des Durchschnittsmolekulargewichts von Organosolvligninen auf das Abbindeverhalten von daraus hergestellten Lignin-Phenolharz-Kombinationen", ADHASION, no. 11, 1983, BERLIN DE, pages 16 - 23 * |
Also Published As
Publication number | Publication date |
---|---|
NO933601D0 (en) | 1993-10-08 |
JPH06506967A (en) | 1994-08-04 |
AU1680792A (en) | 1992-11-17 |
FI934392A0 (en) | 1993-10-06 |
CA2108176A1 (en) | 1992-10-10 |
WO1992018557A1 (en) | 1992-10-29 |
FI934392A (en) | 1993-12-01 |
EP0646148A1 (en) | 1995-04-05 |
NO933601L (en) | 1993-12-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0646148A1 (en) | Improved lignin-based wood adhesives | |
EP0693090A1 (en) | Lignin-based formulations for wood composites | |
US5202403A (en) | Lignin modified phenol-formaldehyde resins | |
US6747076B2 (en) | Furfuryl alcohol and lignin adhesive composition | |
WO1993021260A2 (en) | Lignin in wood composites | |
US4130515A (en) | Lignin-based composition board binder comprising a copolymer of a lignosulfonate, melamine and an aldehyde | |
US4303562A (en) | Lignin-containing resin adhesive | |
JP2010502773A (en) | Novel composite binders with natural compounds for low release products | |
JP2019534345A (en) | Glyoxalized lignin composition | |
IE81045B1 (en) | Modified phenol-aldehyde resin and binder system | |
US5021531A (en) | Method for recovering and using lignin in adhesive resins by extracting demethylated lignin | |
CN112004904A (en) | Adhesive formulations containing lignin | |
US4201700A (en) | Phenol-aldehyde resin composition containing peanut hull extract and an aldehyde | |
US3254038A (en) | Adhesive composition comprising phenolic resin, a tannin and an alkali metal hydroxide | |
US4201851A (en) | Organic phenol extract compositions of pecan pith agricultural residues and method | |
US20220242995A1 (en) | Amino resin performance with sulfonated lignin | |
US4200723A (en) | Organic phenol extract compositions of peanut hull agricultural residues and method | |
CA1068426A (en) | Adhesive for the manufacture of plywood particle boards, fiber boards and similar products | |
US4201699A (en) | Phenol-aldehyde resin composition containing pecan pith extract and an aldehyde | |
FI129584B (en) | Resin composition | |
US3285805A (en) | Polyvalent metal carbonate-extended phenolic resins | |
US4469858A (en) | Tree foliage extracts and their use in phenol-aldehyde resins | |
Schroeder | Method for recovering and using lignin in adhesive resins by extracting demethylated lignin | |
SE192921C1 (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A4 | Supplementary search report drawn up and despatched | ||
AK | Designated contracting states |
Kind code of ref document: A4 Designated state(s): AT CH DE DK ES FR GB IT LI SE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 19931008 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT CH DE DK ES FR GB IT LI SE |
|
17Q | First examination report despatched |
Effective date: 19960313 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED |
|
18R | Application refused |
Effective date: 19980830 |