Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
  • C09C1/36—Compounds of titanium
  • C09C1/3607—Titanium dioxide
  • C09C1/3669—Treatment with low-molecular organic compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K9/00—Use of pretreated ingredients
  • C08K9/04—Ingredients treated with organic substances
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
  • C09C3/08—Treatment with low-molecular-weight non-polymer organic compounds
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2004/00—Particle morphology
  • C01P2004/60—Particles characterised by their size
  • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2004/00—Particle morphology
  • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2004/00—Particle morphology
  • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
  • C01P2004/82—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases
  • C01P2004/84—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases one phase coated with the other
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2006/00—Physical properties of inorganic compounds
  • C01P2006/12—Surface area
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2006/00—Physical properties of inorganic compounds
  • C01P2006/22—Rheological behaviour as dispersion, e.g. viscosity, sedimentation stability
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2006/00—Physical properties of inorganic compounds
  • C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S516/00—Colloid systems and wetting agents; subcombinations thereof; processes of
  • Y10S516/01—Wetting, emulsifying, dispersing, or stabilizing agents
  • Y10S516/07—Organic amine, amide, or n-base containing

Definitions

• This invention relates to surfactant treated particulate titanium dioxide and other pigments. More particularly, this invention is concerned with surfactant treated titanium dioxide and other particulate materials readily employable in coating compositions, plastic molding compositions and reinforced plastic composite compositions.
• Industrial pigment particles agglomerate or cake together into hard packed clusters during the drying operation near the end of the manufacturing process. Forces holding pigment clusters together are not large in many cases but are yet large enough that the pigment user, those who incorporate industrial pigments into their products such as paints and plastics and the like, are required to subject industrial pigments to a milling operation in which the agglomerates are sheared under stress into particles of suitable s allness and homogenized into the matrix or product which incorporates them. The process is dispersion.
• Pigment dispersion ' is a bottleneck, a limiting requirement, and the most expensive operation in terms of energy and time in manufacturing processes which employ pigments.
• This present invention is concerned with the employment of surfactants for the surface treatment of pigments during the pigment manufacturing process in order to provide pigments of improved dispersibility in subsequent manufacturing processes and in some cases, to provide improvements in certan important aspects of products incorporating these surface treated pigments.
• Pigment particle wettability is improved due to a lowering of the interfacial tension between the pigment surface and the application medium.
• Pigments, their preparation and properties are described in volumes I, II and III of the book “Pigment Handbook” published by John Wiley & Sons, Inc. The uses, preparation and characterization of pigments. is further described in the various units of "The Federation Series On Coating Technology” published by the Federation Of Societies For Coating Technology.
• German Patents 889,042 and 930,998 teach the use of surface-active substances as emulsifiers together with oils in the manufacture of water-insoluble azo-dyestuffs having a soft grain.
• U.S. Patent No. 3,120,508 discloses that water-insoluble azo-dyestuffs having a particularly high tinctorial strength •can be prepared by adding during the coupling cationic surfaceactive compounds without simultaneously using oils.
• Cationic surface-active compounds are described in the book "Surface-Active Agents and Detergents" by A.M. Schwartz, J.W. Perry and J. Berch, vol. II (1958), pages 103 to 119.
• Suitable cationic surface-active substances are, for example, long-chained aliphatic a ino compounds that contain about 10 to 18 carbon atoms, or the salts of such nitrogen compounds with carboxylic acids, such for example, as formic acid, acetic acid, oleic acid, tallow fatty acid, lactic acid or mineral acids, for example, hydrochloric acid.
• Fatty amines are for example, coconut oil amine, oleyl amine, stearyl amine, and tallow fat amine, as well as the secondary and tertiary amines or quaternary ammonium compounds derived therefrom that may carry as substituents aliphatic, aromatic or oxethylated radicals, for example, alkyldimethyloxethyla monium chlroide. Oxethylated fatty amines in their secondary, tertiary or quaternary form are also suitable.
• condensation products of long-chained, in some case also unsaturated, carboxylic acids with amines in particular alkylenediamines, alkylenetriamines, or alkylenepolyamines containing alkylene radicals of low molecular weight, for example, ethylene diamine, diethylene triamine, etc., as well as the secondary, tertiary or quaternary amines formed by alkylation of the condensation products, especially in the form of their water-soluble salts with the above-mentioned acids.
• fatty acid amides and esters of long-chained carboxylic acids with ' alkylol amines for example, triethanolaminoleate, stearate, and the like, further also cyclical, nitrogen-containing compounds, for example, long-chained derivatives of morpholine, imidazoline, piperidine, piperazine or pyridine.
• the above-mentioned amino compounds are used preferably in the form of their carboxylic or hydrochloric salts.
• British Patent No. 1,080,115 discloses the use of primary long chain alkyl amines for treating pigments improving their dispersibility
• organosilicon compounds have been employed in the treatment of inorganic oxide surfaces such as inorganic oxide films, particulate fillers and pigments, and fibers (such as glass fibers, aluminum fibers and steel fibers).
• Aluminum and steel fibers are considered oxide surfaces because they are oxidized even though their sub-surfaces are not.
• the typical prior art treatment involved coating such surfaces with hydrolyzate (and/or condensate of hydrolyzate) of an organofunctional hydrolyzable silane.
• surface coating compounds are termed coupling agents and/or adhesion promoters.
• Another conventional technique for supplying the coupling agent to the inorganic oxide surface is by the integral blending technique.
• This technique involves adding to the resin medium the desired amount of the coupling agent and providing the medium in contact with the inorganic oxide surface by supplying the latter as a particulate filler or fiber to the medium or supplying the medium with the coupling agent to a continuous surface in the form of a film, fabric, foil or other shapes, wherein the coupling agent migrates within the medium to contact the surface or surfaces, react thereat and couple with the medium under the molding, curing and other shaping conditions.
• coupling agents enhance the chemical bonding between the medium and the inorganic oxide substrate thereby to achieve improved adhesion between them. This could affect the strength properties of the composite of the plastic or resin associated with the inorganic oxide substrate or substrates.
• Coupling agents have been extensively employed in the surface treatment of inorganic particulate materials such as fillers, pigments, and materials which also act to reinforce the resin or plastic materials in which it is incorporated such as asbestos fibers and relatively short length glass fibers, such as staple glass fibers. All of these have been remedially treated by certain coupling agents. However,- in only rare instances do the coupling agents provide benefits other than increased adhesion. It is traditionally accepted that organosilanes add essentially no benefits to and generally detract from the properties of carbon black when employed in paints, dyes, rubber plastics, etc., even though carbon black contains chemisorbed oxygen.
• surfactants which have the capability of increasing the dispersibility of titanium dioxide and other pigments to which it is supplied.
• the utilization of these surfactants on titanium dioxide results, in many cases, in improved strength properties for the composite in which it is incorporated.
• One of the advantageous features of these surfactants is the fact that they provide to the titanium dioxide, to which it is applied, superior properties in the area of manufacturing when utilized in coating and composite systems.
• Titanium dioxide is an established pigmentary material which can also be employed as a reinforcing filler, albeit an expensive one. It is commonly made by two processes, the chloride process and the sulfate process.
• the chloride process is dry process wherein TiCl. is oxidized to Ti0 2 particles.
• titanium sulfate in solution, is converted by a metathesis reaction to insoluble and particulate titanium dioxide.
• particle formation can be seeded by aluminum compounds. Thereafter, the processes are essentially the same.
• the Ti0 2 particles in a water slurry are put through multiple hydroseparations to separate out the large particles and the further refined pigment in slurry form is passed to a treating tank where the, particles may be treated with an aluminum compound and/or silicon compound, such as aluminum triethoxide, sodium aluminate, aluminum trichloride, aluminum suflate, ethyl silicate, sodium silicate, silicon tetrachloride, trichlorosilane, and the like.
• the pigment is flocculated and precipitated with its coating of alumina and/or silica, or without any coating. It is then made into a • filter cake by a vacuum drying and further dried in an oven, generally of a vibrating type.
• the optimum average particle size can range from about 0.05 to about 0.35 microns with a range of about 0.1 to about 0.25 more preferable.
• the described surfactants are considered to be "dispersion promoters", that is, a material which makes the titanium dioxide more compatible or dispersible within the plastic or resin system in which it is supplied.
• the surfactants used in this invention serve the function of a surface active agent and in another sense they possess the capacity of enhancing bonding between the titanium dioxide and the resin or plastic in which it is provided.
• Such bonding is effected by virtue of interface compatibility, and/or by way of associative or hydrogen bonding or through covalent bonding to the extent (generally a minimal factor) that the surfactant posseses functional moieties of the classical kind found in coupling agents.
• dispersion promoters of this invention are that they alter the surface characteristics of the titanium dioxide or other pigments so that it is more readily and more thoroughly dispersed within the resin or plastic in which it is incorporated, and this serves to enhance the appearance of the. resulting composite and increase the overall strength of the composite when the particulate material employed is one which serves to reinforce the plastic or resin.
• the amount of dispersion promoter provided upon the titanium dioxide particles is that amount which alters the surface characteristics of the particles so that they are more readily dispersed within the resin, plastic, paper making composition or other medium in which they are incorporated.
• the amount- of the dispersion promoter which is supplied to the titanium dioxide may be from as little as about 0.25 weight percent to about 5 weight percent, based upon the weight of the titanium dioxide particles.
• about 0.5 to about 3 weight percent of the dispersion promoter and/or its derivatives is adequate for the purposes of appropriately alterating the surface characteristic of the particles. Most preferred is 2%.
• the amount of dispersion promoter may be from about 1.00 to about 15.0 per cent or higher.
• the amount of dispersion promoter provided when used with carbon black particles is that amount which alters the surface characteristics of the particles so that they are more readily dispersed within the resin, plastic, paper making composition or other medium in which they are incorporated.
• the amount of the dispersion promoter which is supplied to the carbon black may be from as little as about 1.00 weight percent to about 15.0 weight percent, based upon the weight of the carbon black particles.
• about 4.0 to about 10.0 weight percent of the dispersion promoter and/or its derivatives is adequate for the purposes of appropriately ' alterating the surface characteristic of the particles. Most preferred is about 8.0 percent.
• the amount of dispersion promoter provided when an organic pigment is used is that amount which alters the surface characteristics of the pigment so that it is more readily dispersed within the resin, plastic, paper making composition or other medium in which it is incorporated.
• the amount of the dispersion promoter which is supplied to the organic pigment may be from as little as about 1.00 weight percent to about 15.0 weight percent, based upon the weight of the organic pigment.
• about 4.0 to about 10.0 weight percent of the dispersion promoter and/or its derivatives is adequate for the purposes of appropriately alterating the surface characteristic of the pigment. Most preferred is about 8.0 percent.
• the amount of dispersion promoter provided when inert pigments are used, as characterized herein, is that amount which alters the surface characteristics of the pigment so that it is more readily dispersed within the resin, plastic, paper making composition or other medium in which it is incorporated.
• the amount of the dispersion promoter which is supplied to the inert pigment may be from as little as about 0.25 weight percent to about 5 weight percent, based upon the weight of the inert pigment. As a rule, about 0.5 to about 3 weight percent of the dispersion promoter and/or its derivatives is adequate for the purposes of appropriately alterating the surface characteristic of the pigment. Most preferred is 2%.
• the surfactant may be added directly to the plastic, resin or other vehicle containing untreated titanium dioxide particles with improvement in dispersibility.
• the dispersion promoter and/or is derivatives may be provided on the titanium dioxide particles by any of the known methods by which dispersion promoters are similary supplied to particulate surfaces.
• adding the dispersion promoter to the particles while tumbling, mixing the particles in a dilute liquid composition containing the dispersion promoter, or forming a slurry of the particles and dispersion promoter and drying, spray drying or the like represent adequate treating procedures.
• the plastics and/or resin in which the titanium dioxide particles treated with the dispersion promoter and/or its derivatives include essentially any plastic and/or resin. Included in the definition of plastic are rubber compounds.
• the treated titanium dioxide particles may be " supplied to the plastic and/or resin while the same is in any liquid or compoundable form such as a solution/ suspension, latex, dispersion, and the like. It makes no difference from the standpoint of this invention whether the plastic contains solvent or nonsolvent, or the solvent is organic or inorganic except, of course, it would not be desirable for any plastic or resin or any of the treated titanium dioxide to employ a solvating or dispersing medium which deleteriously affects the components being blended.
• Suitable plastics and resins include, by way of example, thermoplastic and thermosetting resins and rubber compounds (including thermoplastic elastomers).
• the plastics and resins containing the treated particles of this invention may be employed, for example, for molding (including extrusion, injection, calendering, casting, compression, lamination, and/or transfer molding), coating (including laquers, film bonding coatings, powder coatings, coatings containing only pigment and resin, and painting,) inks, dyes, tints, impregnations, adhesives, caulks, sealants. rubber goods, and cellular products.
• molding including extrusion, injection, calendering, casting, compression, lamination, and/or transfer molding
• coating including laquers, film bonding coatings, powder coatings, coatings containing only pigment and resin, and painting,
• the plastics and resins may be alkyd resins, oil modified alkyd resins, unsaturated polyesters employed in GRP applications, natural oils, (e.g., linseed, tung, soybean), epoxides, nylons, thermoplastic polyester (e.g., polyethyleneterephthalate, polybutylenetere- phthalate) , polycarbonates, polyethylenes, polybutylenes, polystyrenes, styrene butadiene copolymers, polypropylenes, ethylene propylene co- and terpoly ers, silicone resins and rubbers, SBR rubbers, nitrile rubbers, natural rubbers, acrylics (homopolymer and copolymers of acrylic acid, acrylates, methacrylates, acrylamides, their salts, hydrohalides, etc.), phenolic resins, polyoxymethylene (homopolymers and copolymers), polyurethanes, polysulfones, etc.
• Dry pigments may be reground after aggregation has occurred and thereafter treated with the dispersion promoter of the present invention in a liquid slurry of the pigment.
• the treatment of titanium dioxide with the dispersion promoter during the manufacture of the pigment is most desirable.
• the treatment can take place in the treatment tank or on the filter cake or at any convenient place in the manufacturing process.
• Propylene Glycol or another suitable carrier medium may be advantageously used.
• the Carboxylic Acid has less than 8 carbon atoms.
• the Carboxylic Acid has from 1 to 4 carbon atoms.
• the Fatty Acid has from 8 to 24 carbon atoms.
• the Fatty Acid has from 12 to 18 carbon atoms.
• the Diamine is selectd from the group consisting of Fatty Diamines and Ether Diamines.
• the Fatty Diamines and Ether Diamines have from 8 to 24 carbon atoms.
• the ingredients are blended to produce a surfactant of about 75% solids which is dispersible in water and can be incorporated into pigment "press-cake", the concentrated aqueous phase described above.
• the resulting pigments have markedly improved dispersibility in solvent borne chemical coatings and are suitable for inclusion in water borne coatings conferring important improvements as shown in the Examples.
• the surfactants of the present invention are generally described by the formula:
• Press-cake was first prepared as follows: 800 grams Dupont Ti-pure R-900, or 800 grams Dupont Ti-Pure R-960, or 800 grams Kerr-McGee Tronox CR-800 was ground in a pebble mill with 1200 grams of water for 18-24 hours. (Experiments were carried out with tap water and with deionized water - no difference were detected.) To 250 grams of press-cake, 2.66 grams of Formula A surfactant was added and a slurry formed and contained in a quart can (lined). The slurry was then mixed for 'ten minutes (the press-cake immediately becomes water thin) on a high speed disperser having a 2 inch blade at 1000 RPM.
• treated pigment on solids basis
• Larger quantities of treated pigment may be prepared as follows: disperse the surfactant thoroughly in a small quantity of water and add to press-cake under slow forced movement.
• High speed disperser - 2 inch blade - 1000 RPM - pint can container
• Drill press mixer - 2 1/2 inch round, hollow blade - slowest speed (300-400 RPM) - pint can container Add: 80 grams xylene Add under agitation: 60g 2% treated Kerr-McGee
• High speed disperser - 2 inch blade - 1000 RPM - pint can container
• High speed disperser - 2 inch blade - 1000 RPM - pint can container
• High speed disperser - 2 inch blade - 1000 RPM - pint can container Add and mix 10 minutes: 133g xylene
• Drill press mixer - 2 1/2 inch round, hollow blade - slowest speed (300-400 RPM) - quart can container Add and slurry for one: 132 toluene
• Drill press mixer - 2 1/2 inch round, hollow blade - slowest speed (300-400 RPM) - pint can container Add and slurry two hours: 80g mineral spirits
• Phthalocyanine Blue an organic pigment
• a 4% surfactant treatment was prepared as follows:
• a pint can container was used. lOOg xylene and lOOg Reichold Beckosol .12-054 were mixed well. Then lOg of 4% Phathalo Blue and 300g of 1/8" diameter stainless steel pellets were added and the resultant shaken on a Red Devil Mixer for 10 minutes. Then 0.60g Zirconium (24%), 0.50g Calcium (4%), 0.25g Cobalt (12%), and 0.20g Anti-skin were added and gloss recorded after one minute shaking and after ten additional minutes of shaking.
• the pigment is seen, in thin films, less and less as separate and distinct particles and more and more as ah integral part of the film.
• the surface treated particles are visibly superior in this respect.
• the gloss of the films as dispersion proceeds bears out the superior dispersiblity of the surface treated pigment:
• EXAMPLE 8 Although other carbon black pigments have been successfully treated, the pesent invention has a special affinity for and efficacy in treating the carbon blacks recorded in this Example, perhaps because of the very low pH of these two pigments.
• the carbon black pigment mill bases here described quickly become homogenous, compact, shiny, foamless mixtures which grind quickly and well. This equals 8% (solids) treatment.
• the procedures of Example 2 were followed.
• the resultant was shaken for 2 minutes and gloss recorded: 60° Gloss - 62 .
• the procedure of (3) above was used. lOOg of mineral spirits, lOg of raw Monarch 1300, 2.0g of Nuosperse 657, and 300g of 1/8" diameter stainless steep pellets were added to a pint can and shaken for 30 minutes on a Red Devil Mixer. To the resultant was added lOOg of Beckosol 10-060, 0.6g of 24% Zirconium, 2.0g of 4% Calcium, and 0.25g of 12% Cobalt. The resultant was shaken for 2 minutes and gloss recorded: 60 Gloss - 54 .
• Hegman grind guage reading equals 7-8 Mix separately and combine with the grind portion:
• Hegman equals 7-8 (7-8 Hegman reading is attained much faster than 15 minutes).
• Hegman equals 7-8 (7-8 reading attained in 5 minutes) .
• Hegman equals 7-8 after approximately 5 minutes.
• the surfactants of the present invention have powerful viscosity reducing effects, as shown by the following:
• Adhesion - Water-Borne Formulations Crosshatch Adhesion (ASTM D-2197); Substrate is 1/4" Tempered Masonite Hardboard

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Pigments, Carbon Blacks, Or Wood Stains (AREA)
• Paints Or Removers (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Inks, Pencil-Leads, Or Crayons (AREA)

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• 1985
  • 1985-02-11 US US06/700,891 patent/US4599114A/en not_active Expired - Fee Related
• 1986
  • 1986-02-10 DE DE19863690042 patent/DE3690042T1/de not_active Withdrawn
  • 1986-02-10 WO PCT/US1986/000287 patent/WO1986004598A1/en not_active Ceased
  • 1986-02-10 EP EP86901604A patent/EP0211941A1/en not_active Withdrawn
  • 1986-02-10 AU AU55404/86A patent/AU5540486A/en not_active Abandoned
  • 1986-02-10 GB GB08624299A patent/GB2182028B/en not_active Expired
  • 1986-02-10 CA CA000501504A patent/CA1286941C/en not_active Expired - Lifetime

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