WO2003026878A1 - Molding system with self-releasing moveable member - Google Patents

Molding system with self-releasing moveable member Download PDF

Info

Publication number
WO2003026878A1
WO2003026878A1 PCT/US2002/030551 US0230551W WO03026878A1 WO 2003026878 A1 WO2003026878 A1 WO 2003026878A1 US 0230551 W US0230551 W US 0230551W WO 03026878 A1 WO03026878 A1 WO 03026878A1
Authority
WO
WIPO (PCT)
Prior art keywords
molding system
assemblage
self
molding
moveable member
Prior art date
Application number
PCT/US2002/030551
Other languages
French (fr)
Inventor
Christopher J. Moriarty
Joseph J. Marcinko
Original Assignee
Hunstman International Llc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hunstman International Llc filed Critical Hunstman International Llc
Publication of WO2003026878A1 publication Critical patent/WO2003026878A1/en

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/22Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of indefinite length
    • B29C43/228Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of indefinite length using endless belts feeding the material between non-rotating pressure members, e.g. vibrating pressure members
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/34Feeding the material to the mould or the compression means
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/44Compression means for making articles of indefinite length
    • B29C43/48Endless belts
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/022Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/07Flat, e.g. panels
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28Shaping operations therefor
    • B29C70/40Shaping or impregnating by compression not applied
    • B29C70/50Shaping or impregnating by compression not applied for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
    • B29C70/504Shaping or impregnating by compression not applied for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC] using rollers or pressure bands
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/34Feeding the material to the mould or the compression means
    • B29C2043/3405Feeding the material to the mould or the compression means using carrying means
    • B29C2043/3416Feeding the material to the mould or the compression means using carrying means conveyor belts
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/34Feeding the material to the mould or the compression means
    • B29C2043/3433Feeding the material to the mould or the compression means using dispensing heads, e.g. extruders, placed over or apart from the moulds
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/36Moulds for making articles of definite length, i.e. discrete articles
    • B29C43/3642Bags, bleeder sheets or cauls for isostatic pressing
    • B29C2043/3655Pressure transmitters, e.g. caul plates; pressure pads
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C33/00Moulds or cores; Details thereof or accessories therefor
    • B29C33/56Coatings, e.g. enameled or galvanised; Releasing, lubricating or separating agents
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/36Moulds for making articles of definite length, i.e. discrete articles
    • B29C43/3642Bags, bleeder sheets or cauls for isostatic pressing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C43/00Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
    • B29C43/32Component parts, details or accessories; Auxiliary operations
    • B29C43/52Heating or cooling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29KINDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2075/00Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29KINDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2101/00Use of unspecified macromolecular compounds as moulding material
    • B29K2101/10Thermosetting resins
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29KINDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2311/00Use of natural products or their composites, not provided for in groups B29K2201/00 - B29K2309/00, as reinforcement
    • B29K2311/14Wood, e.g. woodboard or fibreboard

Definitions

  • the present invention relates generally to a molding system, and, more particularly, to a molding system including a moveable member having a self-releasing surface to facilitate a substantial self-release of a consolidated product from the moveable member.
  • consolidated products such as oriented strand board (OSB) are manufactured using wood flakes and formaldehyde-based thermosetting binders such as phenyl formaldehyde.
  • formaldehyde-based thermosetting binders such as phenyl formaldehyde.
  • Isocyanate-based binders particularly diphenylmethane diisocyante (MDI) binders, offer some significant advantages over formaldehyde-based binders, including improved cure time (i.e., substantially faster cure speed), superior physical moisture resistance and the elimination of the formaldehyde emission hazard.
  • isocyanate-based binders have not gained full acceptance, because such isocyanate-containing consolidated products stick to the equipment used for their manufacture (sometimes referred to as the isocyanate-containing composite sticking problem). The removal of these isocyanate-containing consolidated products from the manufacturing equipment damages panels, specifically the panel surfaces.
  • release waxes have also been tried as a release agent. Unfortunately, such waxes build up on the surfaces of equipment resulting in maintenance downtime. Other limitations of release agents include reduction in product quality as a result of an undesirable darkening of the surface of the consolidated product, and high production costs.
  • the present invention is directed to a molding system for working an assemblage including a polymeric component and an isocyanate-based binder into a consolidated product.
  • the molding system includes a molding mechanism and a moveable member having a self-releasing surface for contacting the assemblage while the assemblage is worked into the consolidated product.
  • the self-releasing surface is substantially free of sites capable of reacting with the isocyanate-based binder thereby facilitating a substantial self-release of the consolidated product from the moveable member.
  • the self- releasing surface is made from a material having a standard oxidation potential greater than that of iron.
  • the molding mechanism of the molding system can include a batch press, a continuous press, an extruder or an injection molder.
  • the batch press of the present invention contains an opening for receiving an assemblage and a moveable member.
  • the batch press may further include a plurality of openings for receiving multiple assemblages and a corresponding plurality of moveable members.
  • the continuous press includes an advancement-consolidation mechanism for simultaneously conveying and consolidating the assemblage.
  • the number of moveable members in the continuous press corresponds to the number of advancement- consolidation mechanisms. Examples of advancement-consolidation mechanisms are a chain or a belt.
  • the injection molder in the present invention may include a reaction injection molder.
  • the consolidated product of the present invention may be an engineered lumber product including an oriented strand board (OSB), medium density fiberboard (MDF), or a hard board.
  • OSB oriented strand board
  • MDF medium density fiberboard
  • the engineered lumber product may be shaped as an I-beam, for example, for use as a joist.
  • the engineered lumber product may include a laminated veneer.
  • the polymeric component of the assemblage can include a natural polymer such as a cellulosic, preferably a lignocellulosic. Alternative cellulosics may be, for example, agricultural products.
  • the polymeric component can also include a bark, chip, cork, fiber, flour, particulate, shaving, sheet, strand, wafer, wood wool, and combinations thereof.
  • the polymeric component is any one form of a fiber, particulate, strand, wafer or combinations thereof.
  • the polymeric component of the assemblage may be a synthetic polymer such as a polyolefin.
  • a preferred polyolefin is post consumer waste including textile waste, preferably, fiber.
  • the isocyanate-based binder includes an organic polyisocyanate generally having at least two isocyanate groups.
  • the isocyanate-based binder may further include an additive.
  • an additive that may be added to the assemblage include a mineral filler such as a mica, a glass fiber, and a rubber.
  • the self-releasing surface of the moveable member can be a metal, an alloy or a metalloid, and preferably has a potential greater than about -0.44 volts on the normal hydrogen or standard hydrogen scale.
  • the self-releasing surface may be applied in the molding system as a coating.
  • FIGURE 1 is a schematic of a molding system according to the present invention
  • FIGURE 2 is a diagram of the galvanic series of various metals and alloys and the region within the series usable as the moveable member of the molding system of FIGURE 1;
  • FIGURE 3A is a schematic illustration of using a batch press as the molding mechanism in the molding system of FIGURE 1;
  • FIGURE 3B is a magnified schematic illustration of the batch press FIGURE 3 A;
  • FIGURE 4A is a schematic illustration of using a continuous press as the molding mechanism in the molding system of FIGURE 1;
  • FIGURE 4B is a magnified schematic illustration of a continuous press as may be used in FIGURE 4A;
  • FIGURE 4C is a magnified schematic illustration of an alternative continuous press as may be used in FIGURE 4A;
  • FIGURE 5 is a schematic illustration of an extruder useable as the molding mechanism in the molding system of FIGURE 1;
  • FIGURE 6 is a schematic illustration of a reaction injection molder useable as the molding mechanism in the molding system of FIGURE 1;
  • FIGURE 7 is a photograph of various metal coupons after 10 pressings showing wood remaining thereon;
  • FIGURE 8 is a graph of weight gain per unit area for various coupons as a function of the number of pressings
  • FIGURE 9 is a graph of average weight gain per unit area for various metal coupons under various conditions as a function of the metal's potential ( ⁇ S.H.E); and FIGURE 10 is a graph of average weight gain under various conditions as a function of the metal's potential ( ⁇ S.H.E).
  • FIG. 10 a molding system, generally designated 10, is shown schematically according to the present invention.
  • the molding system 10 includes a moveable member 12 having a self-releasing surface 14.
  • the moveable member 12 may be any one of integral with and additional to a molding mechanism 20.
  • One optional feature of the molding system 10 includes a mixer 40 for combining a polymeric component with an isocyanate-based binder to form an assemblage 16. Further, a polymer supply 42 and a binder supply 44 may come before and be connected to the mixer 40. Following mixer 40 may be a dispensing station 46 and a transporting mechanism 48 (both not shown in Figure 1) for preparing and transporting the assemblage 16 to the molding mechanism 20. Examples of dispensing stations 46 and transporting mechanisms 48 are described and illustrated in U.S. Patent Nos. 4,058,210; 4,284,595; 4,454,940; 4,479,428; 4,506,778; and 4,508,772, the disclosure of each being hereby incorporated by reference herein in its entirety.
  • the release performance of the moveable member 12 is related to the material making up its surface and may be related to a substantial absence of sites capable of reacting with the isocyanate-based binder.
  • materials having surfaces that include a metal hydroxide (MOH) or hydrated metal hydroxide (MOH'HOH) have the capability of reacting with an isocyanate group (R-NCO).
  • MOH metal hydroxide
  • MOH'HOH hydrated metal hydroxide
  • R-NCO isocyanate group
  • a first possibility involves a reaction between an isocyanate group and a metal hydroxide to make a urethane metal complex (R-NH-CO-O-M) according to the equation A that follows:
  • a second possibility involves a reaction between an isocyanate group and a hydrated metal hydroxide to make a polyurea (R-NH-CO- NH-R) n according to the equation B that follows:
  • an isocyanate-based binder may bond directly to the material making up the surface of the moveable member, and when used in the molding system 10, would exhibit the isocyanate containing composite sticking problem.
  • materials being substantially free of sites capable of reacting with the isocyanate-based binder metal are free of the isocyanate containing composite sticking problem.
  • Such materials include components substantially free of hydroxides and hydrated metal hydroxides. Included among such materials are metals, alloys, and metalloids having a standard oxidation potential greater than that of iron.
  • a material's potential is typically expressed with reference to a hydrogen electrode (i.e., 2H + + 2e " ⁇ H 2 ) in which case the material's potential is expressed as volt on the normal hydrogen or standard hydrogen scale, sometimes expressed ⁇ H or ⁇ S.H.E.
  • Applicants have unexpectantly discovered that materials having a potential greater than about -0.44 volts on the normal hydrogen or standard hydrogen scale work well as the self-releasing surface 14 when in contact with an isocyanate containing assemblage.
  • Figure 2 depicts a galvanic series in flowing seawater (about 8-13 ft/s) and a temperature range of about 50-80°F (about 10-27°C) for a variety of metals, alloys, and metalloids.
  • the potential or range of potentials of the metals, alloys, and metalloids are presented on the normal hydrogen or standard hydrogen scale, on the copper-copper sulfate reference electrode scale (i.e., 2H + + 2e " ⁇ H 2 ), the saturated copper-copper sulfate reference electrode scale (i.e., Cu° ⁇ Cu ++ + 2e " ), and the saturated calomet reference electrode scale (i.e., 2Hg + 2C1 ⁇ Hg 2 + 2e " ).
  • Materials situated to the left of the low alloy steel are within the scope of the present invention.
  • such materials include, but are not limited to, brasses, copper bronzes, nickel and its alloys, and titanium.
  • Table 1 below lists alloys in order of the potential (Volts vs. ⁇ S.H.E. Half-Cell Reference Electrode) they exhibit in flowing seawater.
  • Alloys marked “*” may become active and exhibit a potential near -0.5 volts in low- velocity or poorly aerated water and at shielded areas. Alloys having a potential greater than about -0.44 volts on the normal hydrogen or standard hydrogen scale may be suitable for use as the self-releasing surface 14 when making isocyanate containing consolidated product 18.
  • Table 2 lists materials in the order of their relative activity in seawater. The list begins with the more active (anodic) metal and proceeds down to the least active (cathodic) metal of the galvanic series. The list below is the latest galvanic table from MIL-STD-889 where the materials have been numbered according to how they interact in a galvanic couple in the seawater environment.
  • Table 2 is the galvanic series of metals in seawater from Army Missile Command Report RS-TR-67-11, "Practical Galvanic Series.” TABLE 2: GALVANIC TABLE FROM MIL-STD-889
  • the molding system 10 may include a batch press 22 having at least one opening 24 for receiving the assemblage 16 as part of the molding mechanism 20.
  • the moveable member 12 may be a platen, a caul plate or both.
  • Figure 3 A Also shown in Figure 3 A are a dispensing station 46 and transporting mechanism 48.
  • Figure 3B depicts a batch press having multiple openings for receiving assemblage 16 and multiple moveable members 12; the number of moveable members 12 being equal to the number of openings 24. Examples of batch presses 22 usable with the present invention are described and illustrated in U.S. Patent Nos.
  • Figures 4 A, 4B, and 4C depict the molding system 10 as including a continuous press 26 having a molding mechanism and an advancement-consolidation mechanism 28 for simultaneously conveying and consolidating the assemblage 16.
  • the advancement-consolidation mechanism 28 may include a belt 32 or a chain 30.
  • the moveable member 12 may be the advancement-consolidation mechanism 28 having a continuous belt, a chain or mesh, a platen, a caul plate or combinations thereof.
  • a dispensing station 46, transporting mechanism 48, and cutting station 50 for cutting the consolidated product 18 into panels or sheets. Examples of continuous presses 26 usable with the present invention are described and illustrated in U.S. Patent Nos.
  • Figure 5 depicts the molding system 10 as including an extruder 34 as a part of the molding mechanism 20.
  • the moveable member 12 can include a die 52, a mold 54 or both.
  • a transporting mechanism 48 for advancing the assemblage into the die 52 or mold 54.
  • the molding system 10 may include an injection molder 38, preferably a reaction injection molder, as a part of the molding mechanism 20.
  • the moveable member may be a die, a mold or both.
  • polymer supply 42, binder supply 44 and mixer 40 for supplying and combining the polymeric component with the isocyanate-based binder to form the assemblage.
  • the injection molder 38 can further include a dispensing station and a transporting mechanism for advancing the assemblage into the die or mold.
  • An example of an injection molder believed to be usable with the present invention is described and illustrated in U.S. Patent No. 5,770,141, the disclosure being hereby incorporated by reference herein in its entirety.
  • organic polyisocyanates useful in the isocyanate-based binder according to the present invention generally include any organic polyisocyanate compound or mixture of organic polyisocyanate compounds provided the compounds have at least two isocyanate groups.
  • Suitable organic polyisocyanates include diisocyanates, particularly aromatic diisocyanates, and isocyanates of higher functionality.
  • Preferred isocyanates of the present invention include those wherein the isocyanate is an aromatic diisocyanate or polyisocyanate of higher functionality, such as pure diphenylmethane diisocyanate or mixture of methylene bridged polyphenyl polyisocyanates containing diisocyanates, triisocyanates and higher functionality polyisocyanates.
  • Such materials are prepared by the phosgenation of corresponding mixtures of polyamines obtained by condensation of aniline and formaldehyde.
  • polymeric mixtures of methylene bridged polyphenyl polyisocyanates containing diisocyanate, triisocyanate and higher functionality polyisocyanates are referred to hereinafter as "polymeric MDI". Both polymeric MDI and emulsif ⁇ able MDI or aqueous emulsions thereof can be used.
  • the polyisocyanate is liquid at room temperature.
  • Modified polyisocyanates containing isocyanurate, carbodiimide or uretonimine groups may also be used according to the present invention.
  • blocked polyisocyanates such as the reaction product of a phenol or an oxide and a polyisocyanate, having a deblocking temperature below the temperature applied when using the polyisocyanate composition may be utilized as the organic polyisocyanate binder in the present process.
  • the organic polyisocyanate may also be an isocyanate- ended prepolymer prepared by reacting an excess of a diisocyanate or a higher functionality polyisocyanate with a polyol.
  • No. 91/03082 can also be used.
  • isocyanates may also be used in the present process.
  • a mixture of tolylene diisocyanate isomers such as the commercially available mixtures of 2,4- and 2,6-isomers and also the mixture of di- and higher polyisocyanates produced by phosgenation of aniline/formaldehyde condensates may be utilized as the organic polyisocyanate binder according to the present invention.
  • Such mixtures further include the crude phosgenation products containing methylene bridged polyphenylpolyisocyanates, including diisocyanate, triisocyanate and higher polyisocyanates together with any phosgenation by-products.
  • the isocyanate-based binder may further comprise additives conventionally used in the art such as flame retardants, lignocellulosic preserving agents, fungicides, waxes, sizing agents, fillers, catalysts, surfactants and other binders such as formaldehyde condensate adhesives.
  • additives conventionally used in the art such as flame retardants, lignocellulosic preserving agents, fungicides, waxes, sizing agents, fillers, catalysts, surfactants and other binders such as formaldehyde condensate adhesives.
  • the isocyanate-based binder is generally applied to the polymeric component, which is preferably a natural polymer.
  • the natural polymer can include material such as a cellulosic, preferably a lignocellulosic, in an amount of about 0.1% to about 25%, preferably about l%,to about 12% and most preferably about 2% to about 8% by weight based upon the dry weight of the lignocellulosic material.
  • the lignocellulosic material is treated with the isocyanate-based binder material by means of, for example, mixing, blending, spraying and/or spreading the isocyanate-containing composition with or onto the lignocellulosic material.
  • Such application may generally take place in a conventional blender.
  • the treated lignocellulosic material is formed into a mat, preferably upon a screen.
  • the lignocellulosic-containing mat may then be conveyed to a press where pressure is applied thereto at elevated temperatures.
  • the pressing operation generally includes pressing at temperatures of about 120°C to 260°C and at pressures of about 2 to 6 MPa.
  • the consolidation operation may be modified as needed for a particular operation. While the process is particularly suitable for the manufacture of waferboard known extensively as oriented strand board and would largely be used for such manufacture, the process should not be regarded as limited in this regard.
  • the present process can also be used in the manufacture of various types of engineered lumber products, such as, for example, medium density fiberboard, hardboard, particle board (also known as chipboard), plywood, laminated veneer lumber and beams, composite I- beams, and finger jointed lumber.
  • the cellulosic material suitable for use in the present process includes all types known in the industry, such as wood strands, wood chips, wood fibers, shavings, veneers, wood wool, cork, bark, sawdust and similar waste products of the woodworking industry as well as other materials having a lignocellulosic basis such as paper, bagasse, straw, flax, sisal, hemp, rushes, reeds, rice hulls, husks, grass, nutshells and the like.
  • the cellulosic material may be mixed with other particulate or fibrous materials such as mineral fillers, glass fiber, mica, rubber, and textile waste such as plastic fibers, fabrics and plastic particles.
  • the sheets and molded bodies produced according to the present invention have excellent mechanical properties and they may be used in any of the situations where such articles are customarily used.
  • release agents may also still be used to enhance self-release of the assemblage.
  • release agents may be used internally, e.g., as an emulsion or mixture with the organic polyisocyanate or externally, e.g., applied to the self-releasing surface 14 of the moveable member 12 or to the polymeric component of the assemblage 16.
  • the release agent can be used as an internal release agent, in conjunction with the use of an external release agent.
  • release agents include oil, wax polish, metallic soap, silicone such as polysiloxane having isocyanate reactive functional groups, and polytetrafluoroethylene.
  • a common external release agent is based upon fatty acid salts (e.g., potassium oleate, sodium oleate, etc.). Applicants believe that such fatty acid salts are to be used with care since at typical consolidation temperatures discoloration is observed in the consolidated product containing lignocellulosics. To that end the fatty acid salts may be used in an effective amount that is beneficial to the operation of the self-releasing surface 14 of the moveable member 12 while at the same time imparting substantially no discoloration to the consolidated product 18.
  • fatty acid salts e.g., potassium oleate, sodium oleate, etc.
  • Common release agents are wax-based.
  • the binding of lignocellulosic materials with polyisocyanates while using wax-based release agents is described in, for example, EP 46014 EP 57502, U.S. Patent No. 5,554,438 and U.S. Patent No. 5,908,496, the disclosure of each being hereby incorporated by reference herein in its entirety.
  • Wax- based release agents may be used in an effective amount that is both beneficial to the operation of the self-releasing surface 14 of the moveable member 12 while imparting desirable frictional and/or adhesion properties to the surfaces of the consolidated product 18.
  • release agents whether used internally, externally, or internally and externally, are to be used in effective amounts that are beneficial both to the removal of consolidated product 18 from the self-releasing surface 14 of moveable member 12 while at the same time imparting little to no detriment to product physical properties (e.g., surface color, surface grip, surface roughness, surface adhesion, strength, moisture resistance, etc.). Further, the use of release agent would be effective in amounts that provide good release memory and little or no build-up on the self-releasing surface 14 of the moveable member 12.
  • Mats of the blended flakes measuring about 30 x 30 cm were hand formed in a box, on a screen.
  • elementally pure metal samples about 99.99 wt.% from Aldrich Chemical Company, Milwaukee, WI
  • wet about 18 hour water soak
  • dry heated to about 200°C for about two minutes before each pressing
  • no conditioning the metal samples measuring about 25 x 25 x 0.25 mm were placed on the mat surface, where the largest and most uniform aspen flakes were situated.
  • the mats were then pressed in a PLC controlled hotpress at a temperature of about 205°C using a pressing strategy of closing in about 20 seconds, holding for about 100 seconds, and decompressing in about 10 seconds.
  • the mats were pressed to a thickness of about 6.4 mm directly to the steel platen surface that was pre-coated with a release agent. Following pressing, the panels were removed from the press. The metal samples were carefully removed in the direction of the wood grain, and the effort to remove the sample was noted. The weight of wood sticking to each metal sample was measured to about 0.0001 gram with an analytical balance. This was repeated nine times yielding a ten pressing series for each metal type and pre-conditioning.
  • metal hydroxides and adsorbed water e.g., hydrated metal hydroxides
  • isocyanate group play a role in the sticking of isocyanate-based binder consolidated products and, in particular, MDI bonded lignocellulosic consolidated products to metal surfaces.
  • Table 3 contains a summary of properties for comparison of a consolidated product of the present invention with the prior art. Among the properties compared are surface discoloration, surface grip, surface roughness, and surface adhesion.
  • release agents may impart discoloration upon a product.
  • the extent of surface discoloration may be rated as severe, in the worst case, to substantially none in the best case.
  • Colorimetric analysis may be used to quantify the extent to which a product possesses an aesthetically pleasing, light colored surface.
  • Surface grip is inversely related to surface slipperiness.
  • the use of release agents may impart surface slipperiness upon a product. For the most part, surface slipperiness is undesirable and may be accentuated when the product is wet by water. In contrast, surface grip slipperiness is desirable and may be rated as poor, in the worst case when a product is slippery, to excellent when even the wetting by water imparts substantially no slipperiness. Determination of the coefficient of friction may be used to quantify the extent to which a product possesses satisfactory surface grip. As mentioned above, without the use of release agents, almost inevitably a product may be characterized by extensive polymer pullout. Even with the use of release agents, a product may be characterized by moderate polymer pullout.
  • the extent of surface roughness may be rated as extensive, in the worst case, to substantially none in the best case.
  • Surface roughness measurements such as from a profilometer, qualitative visual analysis and even surface sensitive physical properties measurement may be used to quantify the extent to which a product possesses satisfactory surface roughness.
  • Surface adhesion relates the ability of a coating and/or adhesive to remain on a product.
  • release agents may have adverse effects on surface adhesion.
  • the extent of surface adhesion may be rated as poor, in the worst case, to tenacious in the best case. Paint adhesion testing and glue adhesion testing may be used to quantify the extent to which a product possesses satisfactory acceptance to paints and glues.
  • Table 4 contains a summary of a comparison of properties for a consolidated product of the present invention with the prior art.
  • properties compared are surface discoloration, surface grip, surface roughness, surface adhesion and surface performance.
  • Surface performance is the product of surface discoloration, surface grip, surface roughness and surface adhesion.
  • a consolidated product of the present invention including a polymeric component, an isocyanate-based binder, a surface essentially free of a release agent, and a surface performance rating of about 625 is clearly superior over the prior art that at best has a performance rating of about 48.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Dry Formation Of Fiberboard And The Like (AREA)

Abstract

A molding system (10) for working an assemblage (16) including a polymeric component and an isocyanate -based binder into consolidated product . The molding system (10) includes a moveable member (12) and a molding mechanism (20). The molding mechanism has a self-releasing surface for contacting the assemblage while the assemblage is worked into the consolidated product. The self -releasing surface is made from a material having a standard oxidation potential graeter than that of iron so as to be sustantially free of sites capable of reacting with the isocyanate-based binder thereby facilitating a substantial self-release of the consolidated product from the moveable member.

Description

MOLDING SYSTEM WITH SELF-RELEASING MOVEABLE MEMBER
Field of the Invention
The present invention relates generally to a molding system, and, more particularly, to a molding system including a moveable member having a self-releasing surface to facilitate a substantial self-release of a consolidated product from the moveable member.
Background of the Invention For the most part, consolidated products such as oriented strand board (OSB) are manufactured using wood flakes and formaldehyde-based thermosetting binders such as phenyl formaldehyde. Although such formaldehyde-containing consolidated products are characterized by acceptable physical properties, formaldehyde-based binders require an extended cure time, do not possess moisture resistant properties and exhibit a formaldehyde emission hazard.
Isocyanate-based binders, particularly diphenylmethane diisocyante (MDI) binders, offer some significant advantages over formaldehyde-based binders, including improved cure time (i.e., substantially faster cure speed), superior physical moisture resistance and the elimination of the formaldehyde emission hazard. Despite these advantages, isocyanate-based binders have not gained full acceptance, because such isocyanate-containing consolidated products stick to the equipment used for their manufacture (sometimes referred to as the isocyanate-containing composite sticking problem). The removal of these isocyanate-containing consolidated products from the manufacturing equipment damages panels, specifically the panel surfaces. In an attempt to overcome the isocyanate-containing composite sticking problem, producers use a phenyl formaldehyde-based binder for the surface portions and isocyanate-based binders for the core portion of the product. However, this generally results in a lower quality product than one that is bonded entirely with an isocyanate-based binder. In another attempt to overcome the isocyanate-containing composite sticking problem, producers have used release agents. For example, soap-based release agents such as potassium oleate have been sprayed on the surface of a wood flake mat forming a thin physical barrier to prevent sticking. However, soaps do not provide release memory (e.g., if a mat enters the press without a coating, sticking will occur immediately). Polyolefm-based release waxes have also been tried as a release agent. Unfortunately, such waxes build up on the surfaces of equipment resulting in maintenance downtime. Other limitations of release agents include reduction in product quality as a result of an undesirable darkening of the surface of the consolidated product, and high production costs.
Thus, there remains a need for a new and improved molding system that provides a surface to facilitate a substantial self-release of the consolidated product from the molding system without reducing finished product quality.
Summary of the Invention
The present invention is directed to a molding system for working an assemblage including a polymeric component and an isocyanate-based binder into a consolidated product. The molding system includes a molding mechanism and a moveable member having a self-releasing surface for contacting the assemblage while the assemblage is worked into the consolidated product. The self-releasing surface is substantially free of sites capable of reacting with the isocyanate-based binder thereby facilitating a substantial self-release of the consolidated product from the moveable member. Preferably, the self- releasing surface is made from a material having a standard oxidation potential greater than that of iron. The molding mechanism of the molding system can include a batch press, a continuous press, an extruder or an injection molder. The batch press of the present invention contains an opening for receiving an assemblage and a moveable member. The batch press may further include a plurality of openings for receiving multiple assemblages and a corresponding plurality of moveable members. The continuous press includes an advancement-consolidation mechanism for simultaneously conveying and consolidating the assemblage. The number of moveable members in the continuous press corresponds to the number of advancement- consolidation mechanisms. Examples of advancement-consolidation mechanisms are a chain or a belt. The injection molder in the present invention may include a reaction injection molder.
The consolidated product of the present invention may be an engineered lumber product including an oriented strand board (OSB), medium density fiberboard (MDF), or a hard board. Likewise, the engineered lumber product may be shaped as an I-beam, for example, for use as a joist. Alternatively, the engineered lumber product may include a laminated veneer.
The polymeric component of the assemblage can include a natural polymer such as a cellulosic, preferably a lignocellulosic. Alternative cellulosics may be, for example, agricultural products. The polymeric component can also include a bark, chip, cork, fiber, flour, particulate, shaving, sheet, strand, wafer, wood wool, and combinations thereof. Preferably, the polymeric component is any one form of a fiber, particulate, strand, wafer or combinations thereof.
Alternatively, the polymeric component of the assemblage may be a synthetic polymer such as a polyolefin. A preferred polyolefin is post consumer waste including textile waste, preferably, fiber.
The isocyanate-based binder includes an organic polyisocyanate generally having at least two isocyanate groups. The isocyanate-based binder may further include an additive. Examples of an additive that may be added to the assemblage include a mineral filler such as a mica, a glass fiber, and a rubber.
The self-releasing surface of the moveable member can be a metal, an alloy or a metalloid, and preferably has a potential greater than about -0.44 volts on the normal hydrogen or standard hydrogen scale. The self-releasing surface may be applied in the molding system as a coating. These and other aspects of the present invention will become apparent to those skilled in the art after a reading of the following description of the preferred embodiment when considered with the drawings.
Brief Description of the Drawings FIGURE 1 is a schematic of a molding system according to the present invention;
FIGURE 2 is a diagram of the galvanic series of various metals and alloys and the region within the series usable as the moveable member of the molding system of FIGURE 1;
FIGURE 3A is a schematic illustration of using a batch press as the molding mechanism in the molding system of FIGURE 1;
FIGURE 3B is a magnified schematic illustration of the batch press FIGURE 3 A; FIGURE 4A is a schematic illustration of using a continuous press as the molding mechanism in the molding system of FIGURE 1; FIGURE 4B is a magnified schematic illustration of a continuous press as may be used in FIGURE 4A;
FIGURE 4C is a magnified schematic illustration of an alternative continuous press as may be used in FIGURE 4A; FIGURE 5 is a schematic illustration of an extruder useable as the molding mechanism in the molding system of FIGURE 1;
FIGURE 6 is a schematic illustration of a reaction injection molder useable as the molding mechanism in the molding system of FIGURE 1;
FIGURE 7 is a photograph of various metal coupons after 10 pressings showing wood remaining thereon;
FIGURE 8 is a graph of weight gain per unit area for various coupons as a function of the number of pressings;
FIGURE 9 is a graph of average weight gain per unit area for various metal coupons under various conditions as a function of the metal's potential (Φ S.H.E); and FIGURE 10 is a graph of average weight gain under various conditions as a function of the metal's potential (Φ S.H.E).
Detailed Description of the Preferred Embodiment
In the following description, like reference characters designate like or corresponding parts throughout the several views. Also, in the following description, it is to be understood that such terms as "forward," "rearward," "left," "right," "upwardly,"
"downwardly," and the like are words of convenience and are not to be construed as limiting terms.
Referring now to the drawings in general to Figure 1 in particular, it will be understood that the illustrations are for the purpose of describing a preferred embodiment of the invention and are not intended to limit the invention thereto. As best described in Figure 1, a molding system, generally designated 10, is shown schematically according to the present invention. The molding system 10 includes a moveable member 12 having a self-releasing surface 14. The moveable member 12 may be any one of integral with and additional to a molding mechanism 20.
One optional feature of the molding system 10 includes a mixer 40 for combining a polymeric component with an isocyanate-based binder to form an assemblage 16. Further, a polymer supply 42 and a binder supply 44 may come before and be connected to the mixer 40. Following mixer 40 may be a dispensing station 46 and a transporting mechanism 48 (both not shown in Figure 1) for preparing and transporting the assemblage 16 to the molding mechanism 20. Examples of dispensing stations 46 and transporting mechanisms 48 are described and illustrated in U.S. Patent Nos. 4,058,210; 4,284,595; 4,454,940; 4,479,428; 4,506,778; and 4,508,772, the disclosure of each being hereby incorporated by reference herein in its entirety.
With respect to the self-releasing surface 14 of the moveable member 12, we have unexpectedly discovered that the release performance of the moveable member 12 is related to the material making up its surface and may be related to a substantial absence of sites capable of reacting with the isocyanate-based binder. Without wishing to be bound by any particular explanation or scientific theory, applicants believe that materials having surfaces that include a metal hydroxide (MOH) or hydrated metal hydroxide (MOH'HOH) have the capability of reacting with an isocyanate group (R-NCO). A first possibility involves a reaction between an isocyanate group and a metal hydroxide to make a urethane metal complex (R-NH-CO-O-M) according to the equation A that follows:
MOH + R-NCO <→ R-NH-CO-O-M. (A)
A second possibility involves a reaction between an isocyanate group and a hydrated metal hydroxide to make a polyurea (R-NH-CO- NH-R)n according to the equation B that follows:
n(MOHΗOH) + 2n(R-NCO) <→ (R-NH-CO-NH-R)„ + n(MOH) + nCO2. (B)
Through reaction (A) or through reaction (B) followed by reaction (A) an isocyanate-based binder may bond directly to the material making up the surface of the moveable member, and when used in the molding system 10, would exhibit the isocyanate containing composite sticking problem.
To that end, applicants have unexpectedly discovered that materials being substantially free of sites capable of reacting with the isocyanate-based binder metal are free of the isocyanate containing composite sticking problem. Such materials include components substantially free of hydroxides and hydrated metal hydroxides. Included among such materials are metals, alloys, and metalloids having a standard oxidation potential greater than that of iron. A material's potential is typically expressed with reference to a hydrogen electrode (i.e., 2H+ + 2e" <→ H2) in which case the material's potential is expressed as volt on the normal hydrogen or standard hydrogen scale, sometimes expressed ΦH or Φ S.H.E. Applicants have unexpectantly discovered that materials having a potential greater than about -0.44 volts on the normal hydrogen or standard hydrogen scale work well as the self-releasing surface 14 when in contact with an isocyanate containing assemblage.
Figure 2 depicts a galvanic series in flowing seawater (about 8-13 ft/s) and a temperature range of about 50-80°F (about 10-27°C) for a variety of metals, alloys, and metalloids. The potential or range of potentials of the metals, alloys, and metalloids are presented on the normal hydrogen or standard hydrogen scale, on the copper-copper sulfate reference electrode scale (i.e., 2H+ + 2e" <→ H2), the saturated copper-copper sulfate reference electrode scale (i.e., Cu° <→ Cu++ + 2e"), and the saturated calomet reference electrode scale (i.e., 2Hg + 2C1 <→ Hg2 + 2e"). Materials situated to the left of the low alloy steel are within the scope of the present invention. By way of example, such materials include, but are not limited to, brasses, copper bronzes, nickel and its alloys, and titanium.
Table 1 below lists alloys in order of the potential (Volts vs. Φ S.H.E. Half-Cell Reference Electrode) they exhibit in flowing seawater.
Figure imgf000008_0001
Figure imgf000009_0001
Alloys marked "*" may become active and exhibit a potential near -0.5 volts in low- velocity or poorly aerated water and at shielded areas. Alloys having a potential greater than about -0.44 volts on the normal hydrogen or standard hydrogen scale may be suitable for use as the self-releasing surface 14 when making isocyanate containing consolidated product 18.
Table 2 lists materials in the order of their relative activity in seawater. The list begins with the more active (anodic) metal and proceeds down to the least active (cathodic) metal of the galvanic series. The list below is the latest galvanic table from MIL-STD-889 where the materials have been numbered according to how they interact in a galvanic couple in the seawater environment. Table 2 is the galvanic series of metals in seawater from Army Missile Command Report RS-TR-67-11, "Practical Galvanic Series." TABLE 2: GALVANIC TABLE FROM MIL-STD-889
Most Anodic (#1) Most Cathodic
(#92)
1. Magnesium 26. Al 5052-H16 51. Brass (plated) 76. Stainless steel
316L (passive)
2. Mg alloy AZ-31B 27. Tin (plated) 52. Nickel-silver (18% Ni) 77. AM355 (active)
3. Mg alloy HK-31A 28. Stainless steel 430
(active) 53. Stainless steel 78. Stainless steel 202
4. Zinc (hot-dip, die 316L (active) (passive) cast, or plated) 29. Lead
54. Bronze 220 79. Carpenter 20
5. Beryllium (hot 30. Steel 1010 (passive) pressed) 55. Copper 110
31. Iron (cast) 80. AM355 (passive)
6. Al 7072 clad on 56. Red Brass
7075 32. Stainless steel 410 81. A286 (passive) (active) 57. Stainless steel 347
7. Al 2014-T3 (active) 82. Titanium 5A1, 2.5
33. Copper (plated, Sn
8. Al 1160-H14 cast, or wrought) 58. Molybdenum, Commercial pure 83. Titanium 13V,
9. Al 7079-T6 34. Nickel (plated) llCr, 3AI
59. Copper-nickel 715
10. Cadmium (plated) 35. Chromium (annealed)
(Plated) 60. Admiralty brass
11. Uranium 84. Titanium 6AI, 4V
36. Tantalum 61. Stainless steel 202 (solution treated
12. Al 218 (die cast) (active) and aged)
37. AM350 (active)
13. Al 5052-0 62. Bronze, Phosphor 85. Titanium 6AI, 4V
38. Stainless steel 310 534 (B-l) (anneal)
14. Al 5052-H12 (active) m 8Mn
15. Al 5456-0, H353 63. Monel 400 86. Titaniu
39. Stainless steel 301
16. Al 5052-H32 (active) 64. Stainless steel 201 87. Titanium 13V, (active) llCr 3AI (solution nless steel 304 heat treated and
17. Al 1100-0 40. Stai (active) 65. Carpenter 20 aged)
18. Al 3003-H25 (active)
41. Stainless steel 430 88. Titanium 75A
19. Al 6061-T6 (active) 66. Stainless steel 321 (active) 89. AM350 (passive)
20. Al A360 (die cast) 42. Stainless steel 410
(active) 67. Stainless steel 316 90. Silver ,
21. Al 7075-T6 (active)
43. Stainless steel 17- 91. Gold
22. Al 6061-0 7PH (active) 68. Stainless steel 309 92. Graphite
(active)
23. Indium 44. Tungsten
69. Stainless steel 17-
24. Al 2014-0 45. Niobium 7PH (passive)
(columbium) 1%
25. Al 2024-T4 Zr 70. Silicone Bronze 655
46. Brass, Yellow, 268 71. Stainless steel 304 47. Uranium 8% Mo (passive)
48. Brass, Naval, 464 72. Stainless steel 301
49. Yellow Brass (passive)
Stainless steel 321
50. Muntz Metal 280 73. (passive) 74. Stainless steel 201 (passive) 75. Stainless steel 286 (passive) As described in Figures 3A and B, the molding system 10 may include a batch press 22 having at least one opening 24 for receiving the assemblage 16 as part of the molding mechanism 20. In a batch press 22, the moveable member 12 may be a platen, a caul plate or both. Also shown in Figure 3 A are a dispensing station 46 and transporting mechanism 48. Figure 3B depicts a batch press having multiple openings for receiving assemblage 16 and multiple moveable members 12; the number of moveable members 12 being equal to the number of openings 24. Examples of batch presses 22 usable with the present invention are described and illustrated in U.S. Patent Nos. 2,543,582; 2,728,468; 3,565,725; 3,619,450; 3,611,482; 3,824,058; 4,412,801; and 4,846,925, the disclosure of each being hereby incorporated by reference herein in its entirety.
Figures 4 A, 4B, and 4C depict the molding system 10 as including a continuous press 26 having a molding mechanism and an advancement-consolidation mechanism 28 for simultaneously conveying and consolidating the assemblage 16. The advancement-consolidation mechanism 28 may include a belt 32 or a chain 30. Likewise, in a continuous press 26, the moveable member 12 may be the advancement-consolidation mechanism 28 having a continuous belt, a chain or mesh, a platen, a caul plate or combinations thereof. Also shown in Figure 4A are a dispensing station 46, transporting mechanism 48, and cutting station 50 for cutting the consolidated product 18 into panels or sheets. Examples of continuous presses 26 usable with the present invention are described and illustrated in U.S. Patent Nos. 3,120,862; 3,723,230; 3,792,953; 3,851,685; 3,993,426; 4,043,732; 4,213,748; 4,802,837; 5,085,812; 5,185,114; 5,224,367; 5,762,980; 5,788,892; 6,007,320; and 6,190,588B1, the disclosure of each being hereby incorporated by reference herein in its entirety. Figure 5 depicts the molding system 10 as including an extruder 34 as a part of the molding mechanism 20. In extruder 34, the moveable member 12 can include a die 52, a mold 54 or both. Also shown in Figure 5 is a transporting mechanism 48 for advancing the assemblage into the die 52 or mold 54. An example of an extruder 34 believed to be usable with the present invention is described and illustrated in U.S. Patent Nos. 6,247,913; 4,913,863 and 3,095,608, the disclosure of each being hereby incorporated by reference herein in its entirety.
As described in Figure 6, the molding system 10 may include an injection molder 38, preferably a reaction injection molder, as a part of the molding mechanism 20. In an injection molder 38, the moveable member may be a die, a mold or both. Also depicted in Figure 6 is polymer supply 42, binder supply 44 and mixer 40 for supplying and combining the polymeric component with the isocyanate-based binder to form the assemblage. The injection molder 38 can further include a dispensing station and a transporting mechanism for advancing the assemblage into the die or mold. An example of an injection molder believed to be usable with the present invention is described and illustrated in U.S. Patent No. 5,770,141, the disclosure being hereby incorporated by reference herein in its entirety.
The organic polyisocyanates useful in the isocyanate-based binder according to the present invention generally include any organic polyisocyanate compound or mixture of organic polyisocyanate compounds provided the compounds have at least two isocyanate groups. Suitable organic polyisocyanates include diisocyanates, particularly aromatic diisocyanates, and isocyanates of higher functionality.
Preferred isocyanates of the present invention include those wherein the isocyanate is an aromatic diisocyanate or polyisocyanate of higher functionality, such as pure diphenylmethane diisocyanate or mixture of methylene bridged polyphenyl polyisocyanates containing diisocyanates, triisocyanates and higher functionality polyisocyanates. Such materials are prepared by the phosgenation of corresponding mixtures of polyamines obtained by condensation of aniline and formaldehyde. For convenience, polymeric mixtures of methylene bridged polyphenyl polyisocyanates containing diisocyanate, triisocyanate and higher functionality polyisocyanates are referred to hereinafter as "polymeric MDI". Both polymeric MDI and emulsifϊable MDI or aqueous emulsions thereof can be used. Preferably the polyisocyanate is liquid at room temperature.
Other examples of organic polyisocyanates which may be used in the process of the present invention include aliphatic isocyanates such as hexamethylene diisocyanate; aromatic isocyanates, such as m-and p-phenylene diisocyanate, tolylene-2,4- and -2,6- diisocyanate, diphenylmethane-4,4'-diisocyanate, chlorophenylene-2,4-diisocyanate, naphthylene-l,5-diisocyanate, diphenylene-4,4' diisocyanate, 4,4'-diisocyanate-3,3'- dimethyldiphenyl, 3 -methyldiphenylmethane-4,4' -diisocyanate and diphenyl ether diisocyanate; and cycloaliphatic diisocyanates such as cyclohexane-2,4- and -2,3- diisocyanate, l-methylcyclohexyl-2,4- and -2,6-diisocyanate and mixtures thereof and bis-(isocyanatocyclohexyl)methane and triisocyanates such as 2,4,6-triisocyanatotoluene and 2,4,4-triisocyanatodiphenylether. Modified polyisocyanates containing isocyanurate, carbodiimide or uretonimine groups may also be used according to the present invention. Furthermore, blocked polyisocyanates, such as the reaction product of a phenol or an oxide and a polyisocyanate, having a deblocking temperature below the temperature applied when using the polyisocyanate composition may be utilized as the organic polyisocyanate binder in the present process. The organic polyisocyanate may also be an isocyanate- ended prepolymer prepared by reacting an excess of a diisocyanate or a higher functionality polyisocyanate with a polyol.
Water-emulsifiable organic polyisocyanates like those described in UK Patent No. 1,444,933; in European Patent Publication No. 516361; and in PCT Patent Publication
No. 91/03082 can also be used.
Mixtures of isocyanates may also be used in the present process. For example, a mixture of tolylene diisocyanate isomers, such as the commercially available mixtures of 2,4- and 2,6-isomers and also the mixture of di- and higher polyisocyanates produced by phosgenation of aniline/formaldehyde condensates may be utilized as the organic polyisocyanate binder according to the present invention. Such mixtures further include the crude phosgenation products containing methylene bridged polyphenylpolyisocyanates, including diisocyanate, triisocyanate and higher polyisocyanates together with any phosgenation by-products. The isocyanate-based binder may further comprise additives conventionally used in the art such as flame retardants, lignocellulosic preserving agents, fungicides, waxes, sizing agents, fillers, catalysts, surfactants and other binders such as formaldehyde condensate adhesives.
The isocyanate-based binder is generally applied to the polymeric component, which is preferably a natural polymer. The natural polymer can include material such as a cellulosic, preferably a lignocellulosic, in an amount of about 0.1% to about 25%, preferably about l%,to about 12% and most preferably about 2% to about 8% by weight based upon the dry weight of the lignocellulosic material.
According to one aspect of the present invention, the lignocellulosic material is treated with the isocyanate-based binder material by means of, for example, mixing, blending, spraying and/or spreading the isocyanate-containing composition with or onto the lignocellulosic material. Such application may generally take place in a conventional blender. Thereafter, the treated lignocellulosic material is formed into a mat, preferably upon a screen. The lignocellulosic-containing mat may then be conveyed to a press where pressure is applied thereto at elevated temperatures. The pressing operation generally includes pressing at temperatures of about 120°C to 260°C and at pressures of about 2 to 6 MPa. It will be recognized by those skilled in the art that the consolidation operation may be modified as needed for a particular operation. While the process is particularly suitable for the manufacture of waferboard known extensively as oriented strand board and would largely be used for such manufacture, the process should not be regarded as limited in this regard. The present process can also be used in the manufacture of various types of engineered lumber products, such as, for example, medium density fiberboard, hardboard, particle board (also known as chipboard), plywood, laminated veneer lumber and beams, composite I- beams, and finger jointed lumber.
The cellulosic material suitable for use in the present process includes all types known in the industry, such as wood strands, wood chips, wood fibers, shavings, veneers, wood wool, cork, bark, sawdust and similar waste products of the woodworking industry as well as other materials having a lignocellulosic basis such as paper, bagasse, straw, flax, sisal, hemp, rushes, reeds, rice hulls, husks, grass, nutshells and the like. Moreover, the cellulosic material may be mixed with other particulate or fibrous materials such as mineral fillers, glass fiber, mica, rubber, and textile waste such as plastic fibers, fabrics and plastic particles. The sheets and molded bodies produced according to the present invention have excellent mechanical properties and they may be used in any of the situations where such articles are customarily used.
Although the molding system 10 having a moveable member 12 with a self-releasing surface 14 of the present invention is directed to minimizing or eliminating the need for release agents, release agents may also still be used to enhance self-release of the assemblage. For example, release agents may be used internally, e.g., as an emulsion or mixture with the organic polyisocyanate or externally, e.g., applied to the self-releasing surface 14 of the moveable member 12 or to the polymeric component of the assemblage 16. According to another aspect of the invention the release agent can be used as an internal release agent, in conjunction with the use of an external release agent.
Examples of release agents include oil, wax polish, metallic soap, silicone such as polysiloxane having isocyanate reactive functional groups, and polytetrafluoroethylene. A common external release agent is based upon fatty acid salts (e.g., potassium oleate, sodium oleate, etc.). Applicants believe that such fatty acid salts are to be used with care since at typical consolidation temperatures discoloration is observed in the consolidated product containing lignocellulosics. To that end the fatty acid salts may be used in an effective amount that is beneficial to the operation of the self-releasing surface 14 of the moveable member 12 while at the same time imparting substantially no discoloration to the consolidated product 18.
Common release agents are wax-based. The binding of lignocellulosic materials with polyisocyanates while using wax-based release agents is described in, for example, EP 46014 EP 57502, U.S. Patent No. 5,554,438 and U.S. Patent No. 5,908,496, the disclosure of each being hereby incorporated by reference herein in its entirety. Wax- based release agents may be used in an effective amount that is both beneficial to the operation of the self-releasing surface 14 of the moveable member 12 while imparting desirable frictional and/or adhesion properties to the surfaces of the consolidated product 18.
In general, release agents, whether used internally, externally, or internally and externally, are to be used in effective amounts that are beneficial both to the removal of consolidated product 18 from the self-releasing surface 14 of moveable member 12 while at the same time imparting little to no detriment to product physical properties (e.g., surface color, surface grip, surface roughness, surface adhesion, strength, moisture resistance, etc.). Further, the use of release agent would be effective in amounts that provide good release memory and little or no build-up on the self-releasing surface 14 of the moveable member 12.
The following examples are provided to help illustrate certain aspects of the present invention and should be in no way viewed as limiting the scope of the present invention.
Examples
Various metals were pressed on the surface of pMDI bonded consolidated product to evaluate a metal's propensity to stick to the consolidated product. Polymer-isocyanate- based assemblages were prepared using dried wood strands blended with about 4 weight percent (wt.%) pMDI (RUBLNATE®M isocyanate, commerically available from
Huntsman International LLC) in a rotary laboratory blender at a rate of 100 grams per minute. A standard slack sizing wax was then spray atomized on the flakes. The mix comprised: about 5 Kg Aspen (Ainsworth Lumber) wood flakes (5.5% MC); about 200 grams pMDI (RUBLNATE®M isocyanate); and about 50 grams slack paraffin wax.
Mats of the blended flakes measuring about 30 x 30 cm were hand formed in a box, on a screen. Prior to pressing, elementally pure metal samples (about 99.99 wt.% from Aldrich Chemical Company, Milwaukee, WI) were conditioned to simulate three moisture conditions; wet (about 18 hour water soak), dry (heated to about 200°C for about two minutes before each pressing), and no conditioning. After conditioning, the metal samples measuring about 25 x 25 x 0.25 mm were placed on the mat surface, where the largest and most uniform aspen flakes were situated. The mats were then pressed in a PLC controlled hotpress at a temperature of about 205°C using a pressing strategy of closing in about 20 seconds, holding for about 100 seconds, and decompressing in about 10 seconds. The mats were pressed to a thickness of about 6.4 mm directly to the steel platen surface that was pre-coated with a release agent. Following pressing, the panels were removed from the press. The metal samples were carefully removed in the direction of the wood grain, and the effort to remove the sample was noted. The weight of wood sticking to each metal sample was measured to about 0.0001 gram with an analytical balance. This was repeated nine times yielding a ten pressing series for each metal type and pre-conditioning.
It was found that certain metals are more likely to "stick" to MDI bonded consolidated product. Wood fiber tore away from the consolidated products and adhered to the metal coupons resulting in weight gain as may be seen in Figure 7. The amount of wood adhering to a metal coupon surface is graphed versus the number of pressings in
Figure 8.
When the data was regraphed as shown in Figures 9 and 10, it is observed that a relationship exists between a metal material's electrochemical potential (Φ S.H.E.) and lignocellulosic consolidated product sticking. That is as the metal material's potential exceeded -0.44 volts, sticking was reduced. In addition, it is observed that as a metal coupon's conditions go from dry to wet, the propensity for sticking increases, and wood failure weight gain increases. For these reasons, applicants believe that the reactivity between metal hydroxides and adsorbed water (e.g., hydrated metal hydroxides), and the isocyanate group, play a role in the sticking of isocyanate-based binder consolidated products and, in particular, MDI bonded lignocellulosic consolidated products to metal surfaces.
Further, applicants believe that the use of the present invention produces a consolidated product that is substantially superior to that of the prior art. Table 3 contains a summary of properties for comparison of a consolidated product of the present invention with the prior art. Among the properties compared are surface discoloration, surface grip, surface roughness, and surface adhesion.
As mentioned above, the use of release agents may impart discoloration upon a product. The extent of surface discoloration may be rated as severe, in the worst case, to substantially none in the best case. Colorimetric analysis may be used to quantify the extent to which a product possesses an aesthetically pleasing, light colored surface.
Surface grip is inversely related to surface slipperiness. The use of release agents may impart surface slipperiness upon a product. For the most part, surface slipperiness is undesirable and may be accentuated when the product is wet by water. In contrast, surface grip slipperiness is desirable and may be rated as poor, in the worst case when a product is slippery, to excellent when even the wetting by water imparts substantially no slipperiness. Determination of the coefficient of friction may be used to quantify the extent to which a product possesses satisfactory surface grip. As mentioned above, without the use of release agents, almost inevitably a product may be characterized by extensive polymer pullout. Even with the use of release agents, a product may be characterized by moderate polymer pullout. The extent of surface roughness may be rated as extensive, in the worst case, to substantially none in the best case. Surface roughness measurements such as from a profilometer, qualitative visual analysis and even surface sensitive physical properties measurement may be used to quantify the extent to which a product possesses satisfactory surface roughness.
Surface adhesion relates the ability of a coating and/or adhesive to remain on a product. The use of release agents may have adverse effects on surface adhesion. The extent of surface adhesion may be rated as poor, in the worst case, to tenacious in the best case. Paint adhesion testing and glue adhesion testing may be used to quantify the extent to which a product possesses satisfactory acceptance to paints and glues.
Figure imgf000018_0001
Table 4 contains a summary of a comparison of properties for a consolidated product of the present invention with the prior art. Among the properties compared are surface discoloration, surface grip, surface roughness, surface adhesion and surface performance. Surface performance is the product of surface discoloration, surface grip, surface roughness and surface adhesion. A consolidated product of the present invention including a polymeric component, an isocyanate-based binder, a surface essentially free of a release agent, and a surface performance rating of about 625 is clearly superior over the prior art that at best has a performance rating of about 48.
Figure imgf000018_0002
Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims.

Claims

ClaimsWHAT IS CLAIMED IS:
1. A molding system for forming a consolidated product from an assemblage having a polymeric component and an isocyanate-based binder, the molding system comprising a moveable member having a self-releasing surface for contacting the assemblage while the assemblage is formed into the consolidated product, the self-releasing surface comprising a material substantially free of sites capable of reacting with the isocyanate-based binder of the assemblage thereby facilitating a substantial self-release of the consolidated product from the moveable member.
2. The molding system of claim 1 wherein the molding system further includes a molding mechanism.
3. The molding system of claim 2 wherein the molding mechanism is a batch press having at least one opening for receiving the assemblage, and wherein the number of moveable members is equal to the number of openings.
4. The molding system of claim 2 wherein the molding mechanism is a continuous press comprising an advancement-consolidation mechanism.
5. The molding system of claim 2 wherein the molding mechanism is an extruder.
6. The molding system of claim 2 wherein the molding mechanism is an injection molder.
7. The molding system of claim 1 wherein the consolidated product is an engineered lumber product.
8. The molding system of claim 1 wherein the polymeric component of the assemblage comprises a natural polymer.
9. The molding system of claim 1 wherein the polymeric component of the assemblage comprises a synthetic polymer.
10. The molding system of claim 1 wherein the isocyanate-based binder comprises an organic polyisocyanate having at least two isocyanate groups.
11. The molding system of claim 1 wherein the assemblage further includes an additive.
12. A molding system for working an assemblage including a polymeric component and an isocyanate-based binder into a consolidated product, the molding system comprising:
(a) a molding mechanism; and
(b) a moveable member having a self-releasing surface for contacting the assemblage while the assemblage is worked into the consolidated product, the self-releasing surface comprising a material having a standard oxidation potential greater than that of iron so as to be substantially free of sites capable of reacting with the isocyanate-based binder thereby facilitating a substantial self-release of the consolidated product from the moveable member.
13. The molding system of claim 12 wherein the molding mechanism is a batch press having at least one opening for receiving the assemblage, and wherein the number of moveable members is equal to the number of openings.
14. The molding system of claim 12 wherein the molding mechanism is a continuous press comprising an advancement-consolidation mechanism.
15. The molding system of claim 12 wherein the molding mechanism is an extruder.
16. The molding system of claim 12 wherein the molding mechanism is an injection molder.
17. The molding system of claim 12 wherein the consolidated product is an engineered lumber product.
18. The molding system of claim 12 wherein the polymeric component of the assemblage comprises a natural polymer.
19. The molding system of claim 12 wherein the polymeric component of the assemblage comprises a synthetic polymer.
20. The molding system of claim 12 wherein the isocyanate-based binder comprises an organic polyisocyanate having at least two isocyanate groups.
21. The molding system of claim 12 wherein the assemblage further includes an additive.
22 The molding system of claim 12 wherein the material of the self-releasing surface has a potential greater than -0.44 volts on a normal hydrogen scale or a standard hydrogen scale.
23. The molding system of claim 22 wherein the material of the self-releasing surface is selected from the group consisting of brass, copper, bronze, nickel, nickel alloy and titanium.
24. A moveable member for use in a molding system comprising a self- releasing surface for contacting an assemblage while the assemblage is worked into a consolidated product, the self-releasing surface comprising a material having a standard oxidation potential greater than that of iron.
25. The moveable member of claim 24 wherein the self-releasing surface has a potential greater than about -0.44 volts on a normal hydrogen or a standard hydrogen scale.
26. The moveable member of claim 24 wherein the material of the self- releasing surface is selected from the group consisting of a metal, an alloy and a metalloid.
27. A method for working an assemblage including a polymeric component and an isocyanate-based binder into a consolidated product, the method comprising:
(a) providing a molding system including a moveable member having a self- releasing surface comprising a material substantially free of sites capable of reacting with the isocyanate-based binder; (b) contacting the assemblage with the self-releasing surface of the moveable member to work the assemblage into the consolidated product; and (c) substantially self-releasing the consolidated product from the moveable member.
28. The method of claim 27 wherein the material of the self-releasing surface has a standard oxidation potential greater than that of iron.
29. The method of claim 28 wherein the material of the self-releasing surface has a potential greater than about -0.44 volts on a normal hydrogen scale or a standard hydrogen scale.
30. A consolidated product made by a process comprising the following steps:
(a) providing a molding mechanism and a moveable member having a self-releasing surface comprising a material having a standard oxidation potential greater than that of iron;
(b) contacting an assemblage comprising a polymeric component and an isocyanate-based binder with the self-releasing surface of the moveable member;
(c) operating the molding mechanism and moveable member to work the assemblage into the consolidated product; and
(d) substantially self-releasing the consolidated product from the moveable member.
31. The consolidated product of claim 30 wherein the consolidated product is any one of a medium density fiberboard, hardboard, particle board, plywood, laminated veneer lumber, laminated beam, composite I-beams, and finger jointed lumber.
PCT/US2002/030551 2001-09-26 2002-09-26 Molding system with self-releasing moveable member WO2003026878A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US32487501P 2001-09-26 2001-09-26
US60/324,875 2001-09-26

Publications (1)

Publication Number Publication Date
WO2003026878A1 true WO2003026878A1 (en) 2003-04-03

Family

ID=23265475

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2002/030551 WO2003026878A1 (en) 2001-09-26 2002-09-26 Molding system with self-releasing moveable member

Country Status (1)

Country Link
WO (1) WO2003026878A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1878551A1 (en) * 2006-07-14 2008-01-16 Schmidt & Heinzmann GmbH & Co. KG Device for conveying a molten material string
US9540513B2 (en) 2012-11-21 2017-01-10 Basf Se Lignocellulosic article and method of producing same

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3824058A (en) * 1972-01-08 1974-07-16 Siempelkamp Gmbh & Co Apparatus for the production of pressed board
US4284595A (en) * 1979-01-19 1981-08-18 Morrison-Knudsen Forest Products Company, Inc. Orientation and deposition of fibers in the manufacture of fiberboard
US4412801A (en) * 1980-05-02 1983-11-01 G. Siempelkamp Gmbh & Co. Pressed-board plant with multilevel press
US4802837A (en) * 1986-11-14 1989-02-07 Kurt Held Apparatus for producing processed wood material panels
US5149391A (en) * 1988-12-09 1992-09-22 Allied-Signal Inc. Prepreg machine with a single endless conveyor belt
US5770141A (en) * 1994-05-27 1998-06-23 Bayer Aktiengesellschaft Process for the production of a filled reaction mixture
US6136408A (en) * 1997-11-25 2000-10-24 J. M. Huber Corporation Surface treatment for wood materials including oriented strand board
US6247913B1 (en) * 1998-05-01 2001-06-19 Nissei Plastic Industrial Co., Ltd. Molding machine

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3824058A (en) * 1972-01-08 1974-07-16 Siempelkamp Gmbh & Co Apparatus for the production of pressed board
US4284595A (en) * 1979-01-19 1981-08-18 Morrison-Knudsen Forest Products Company, Inc. Orientation and deposition of fibers in the manufacture of fiberboard
US4412801A (en) * 1980-05-02 1983-11-01 G. Siempelkamp Gmbh & Co. Pressed-board plant with multilevel press
US4802837A (en) * 1986-11-14 1989-02-07 Kurt Held Apparatus for producing processed wood material panels
US5149391A (en) * 1988-12-09 1992-09-22 Allied-Signal Inc. Prepreg machine with a single endless conveyor belt
US5770141A (en) * 1994-05-27 1998-06-23 Bayer Aktiengesellschaft Process for the production of a filled reaction mixture
US6136408A (en) * 1997-11-25 2000-10-24 J. M. Huber Corporation Surface treatment for wood materials including oriented strand board
US6247913B1 (en) * 1998-05-01 2001-06-19 Nissei Plastic Industrial Co., Ltd. Molding machine

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1878551A1 (en) * 2006-07-14 2008-01-16 Schmidt & Heinzmann GmbH & Co. KG Device for conveying a molten material string
US9540513B2 (en) 2012-11-21 2017-01-10 Basf Se Lignocellulosic article and method of producing same

Similar Documents

Publication Publication Date Title
US4414361A (en) Organic polyisocyanate-cyclic alkylene carbonate adhesive binder compositions
US4359507A (en) Mixed ethylene and propylene carbonate-containing organic polyisocyanate adhesive binder composition
US5908496A (en) Process for binding lignocellulosic material
EP1425144B1 (en) Release agent for lignocellulosic composites
AU733473B2 (en) Process for binding lignocellulosic material
CA2740674A1 (en) Polyisocyanate composition used for binding lignocellulosic materials
CA1173583A (en) Organic polyisocyanate-alkylene oxide adhesive composition for preparing lignocellulosic composite products
US20030015122A1 (en) Fatty acid and polyolefin wax release agent
WO2003026878A1 (en) Molding system with self-releasing moveable member
EP0708789B1 (en) Polyisocyanate composition
US5340852A (en) Polyisocyanate composition
CA2397210A1 (en) Fatty acid and polyolefin wax release agent
EP1161331A1 (en) Processes for preparing molded composite material using wax-based release agents
US9540513B2 (en) Lignocellulosic article and method of producing same
CA2037342A1 (en) Process for preparing lignocellulosic bodies
AU683343B2 (en) Process for the preparation of lignocellulosic bodies
KR20000011065A (en) Process for binding lignocellulosic material
CA2172072A1 (en) Compatibilising agents
MXPA98009824A (en) Process for aggluting lignocellules material

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BY BZ CA CH CN CO CR CU CZ DE DM DZ EC EE ES FI GB GD GE GH HR HU ID IL IN IS JP KE KG KP KR LC LK LR LS LT LU LV MA MD MG MN MW MX MZ NO NZ OM PH PL PT RU SD SE SG SI SK SL TJ TM TN TR TZ UA UG US UZ VN YU ZA ZM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ UG ZM ZW AM AZ BY KG KZ RU TJ TM AT BE BG CH CY CZ DK EE ES FI FR GB GR IE IT LU MC PT SE SK TR BF BJ CF CG CI GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP