Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M111/00—Lubrication compositions characterised by the base-material being a mixture of two or more compounds covered by more than one of the main groups C10M101/00 - C10M109/00, each of these compounds being essential
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
  • F16C33/02—Parts of sliding-contact bearings
  • F16C33/04—Brasses; Bushes; Linings
  • F16C33/20—Sliding surface consisting mainly of plastics
  • F16C33/201—Composition of the plastic
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/04—Elements
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/04—Elements
  • C10M2201/041—Carbon; Graphite; Carbon black
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/04—Elements
  • C10M2201/041—Carbon; Graphite; Carbon black
  • C10M2201/042—Carbon; Graphite; Carbon black halogenated, i.e. graphite fluoride
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/04—Elements
  • C10M2201/05—Metals; Alloys
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/06—Metal compounds
  • C10M2201/061—Carbides; Hydrides; Nitrides
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/06—Metal compounds
  • C10M2201/062—Oxides; Hydroxides; Carbonates or bicarbonates
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/06—Metal compounds
  • C10M2201/065—Sulfides; Selenides; Tellurides
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/06—Metal compounds
  • C10M2201/065—Sulfides; Selenides; Tellurides
  • C10M2201/066—Molybdenum sulfide
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/085—Phosphorus oxides, acids or salts
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/10—Compounds containing silicon
  • C10M2201/105—Silica
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/16—Carbon dioxide
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2201/00—Inorganic compounds or elements as ingredients in lubricant compositions
  • C10M2201/18—Ammonia
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2217/00—Organic macromolecular compounds containing nitrogen as ingredients in lubricant compositions
  • C10M2217/04—Macromolecular compounds from nitrogen-containing monomers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • C10M2217/044—Polyamides
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2217/00—Organic macromolecular compounds containing nitrogen as ingredients in lubricant compositions
  • C10M2217/04—Macromolecular compounds from nitrogen-containing monomers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • C10M2217/045—Polyureas; Polyurethanes
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
  • C10N2040/00—Specified use or application for which the lubricating composition is intended
  • C10N2040/02—Bearings

Definitions

• This invention relates, generally, to the preparation of self-lubricating composites and, more particularly, to the preparation of solid composites which are capable of withstanding loads in excess of 4,000 psi at temperatures which exceed 500°P.
• This invention embodies the provision of a tailorable self-lubricating composite for use in the fabrication of bearings, bushings, and other structural components that are intended for use under dynamic loads which exceed 4,000 psi and operate at temperatures in excess of 500°F.
• These composites must have low wear rates, low coefficients of friction, high compressive strength, and high oxidative stability in air at temperatures which range from 500°F to 600°F and above.
• the "111" Bilow-Gardos patent teaches self-lubricating composites comprising cured acetylene- terminated polymide oligomers filled with molybdenum disulfide, or various other chalcogenides, such as tungsten disulfide, tungsten diselenide, and molybdenum diselenide, in concentrations up to 70? by weight. While the self-lubricating eomposites of the "111" patent exhibit high temperature stabilities, these composites are incapable of sustained operations at loads which exceed 4,000 psi. '
• the general purpose of this invention is to provide a tailorable self-lubricating solid composite for use as bearings, bushings, bearing-retainers, and other structural lubricative elements under operational conditions which may exceed 172 MPa and temperatures of 500°F.
• a tailorable high load capacity, high temperature self-lubricating solid composite by combining a multi-dimensional weave preform, prepared from carbon fibers, graphite fibers, or a combination thereof which. are subsequently modified by the addition of an adjuvant, with a high temperature resin that is filled with lubricative pigments that are oxidatively stable in air up to 1,000°F.
• Self-lubricating composites prepared in accordance with our invention may be tailored through the use of a characteristic wear equation to provide lubricative surfaces under a broad spectrum of conditions wherein the load factors range from ambient pressures to 25,000 psi and the operating temperatures ranges from room ambient temperature to as high as 600°F.
• a further purpose of this invention is to provide tailorable self-lubricating composites for use in the fabrication of bearings, bearing-bushings, bearing retainers, and other structural lubricative elements.
• a still further purpose of this invention is to provide a process for preparing self-lubricating solid composites to be used as bearings, bearing bushings, bearing retainers and other structural lubricative elements.
• FIG. 1 is a schematic flow chart which shows the process of preparing a self-lubricating composite from a woven preform.
• the term "preform”, as used herein, is intended to refer to a woven fiber fabric or cloth which has a pre- determined weave geometry. Woven preforms are commercially available as two directional (2-D), three directional (3-D), or as multi-directional (4-D, 5-D, 7-D . . .
• 11-D fabrics can be prepared from numerous materials such as quartz, fiberglass, zirconia, boron, boron nitride, Silicon Carbide, Carbon, Graphite, High Modulus Fibers, tungsten, stainless steel, metal-graphite, multi-yarns and ceramic fibers.
• These materials are generally formed from pulverized compacts comprising elements found in Groups V and VI (Rows 4-5) of the periodic chart and include, but are not United to, for example, the sulfides, oxides, and selenides of Tungsten, Indium, Molyddenum, Gallium, and Antimony.
• the most suitable lubricative pigment for our purposes was obtained by pulmerizing a Ga/In/WSe 2 compact, known as the Westinghouse Compact, into particles whose diameters ranged essentially from 5 to 10 ym.
• Other compacts of Mo/Nb/Cu/MoS 2 (Hard Molalloy) and MoS 2 /T 2 (Soft Molalloy) may be used for select applications where the performance parameters are less demanding.
• the final element of our composite is the resin which acts as a binder for the system.
• polyimide oligomers prepared in accordance with the teachings of U.S. Patent No's. 3,845,018 (Thermid 600) and 3,879,349 issued to Norman Bilow et al.
• oligomers are acetylene terminated polyimides which undergo additional polymerization without the evolution of void forming gaseous by-products. They are exceptionally stable at high temperatures and polymerized into exceptionally strong polymeric materials.
• U.S. Patent No's. 3,845,018 and 3,879,349 herein for the purpose of enabling others to make and utilize our self-lubrieating composites with the resins disclosed therein. While our studies have shown that acetylene terminated polyimide oligomers are preferred for the invention, other high temperature, stable, structurally strong and chemically inert resins may be employed and are not excluded from consideration or use in any particular combination which follows the teachings as set forth herein. Included as possible resins are any improved versions of Thermid 600, the second generation NASA Lewis PMR polyimide oligomers which cure via addition reactions into relatively stable high temperature polymers or resins.
• Our lubricant composites generally are comprised of a loosely woven preform of selected carbon or graphitic fibers stabilized with up to two percent by weight of NH 2 HPO 4 , filled with from 20 to 30 percent lubricating pigment and bound with from 30-45% resin.
• the corapressive strength, hardness and density of the composites bear directly upon the average wear rates under specified conditions and other parameters such as average friction values. For example, as shown In Table 2, wear rates of from 1.3 x 10 -8 to 3.2 x 10 -8 millimeters per sec (m. sec -1 ) were exhibited at 316°C under 11.03 MPa by solid lubricative composites prepared in accordance with our Invention utilizing two different preforms.
• A contact area (in 2 )
• P composite density lbm. in -3
• P unit load
• V average oscillatory velocity (ft. mln- 1 )
• T duration of sliding (hours)
• FIGS. 1 and la Includes the various stations of the present process which are identified by legend understood by those skilled in the art, and which stations include reference numerals used below in correlating the following Individual process steps with these figures. This legend is Intended to refer only functionally to these various individual process steps and does not in any way limit such steps or stations to any particular apparatus or hardware for carrying out such steps. Obviously, the selection of the particular equipment for performing these steps may be made by those skilled In the art.
• Our preferred compacts 10 may be obtained from Westing- house Corporation and contain Ga:In:WSe2 in a 8:2:90 molar ratio. The materials are pulverized 11 in a colloidal mill to produce a particulate material 12 that is subsequently sifted and screened 12 to yield a lubricative pigment powder 14 having the following particle size distribution as determined by particle size analyses 15.
• Preselected amounts of the pigment particles are then added 16, along with an adjuvant 17, in an amount not to exceed 2% , to a selected 18 amount of resin
• oligomer 19 in a mixer 20 and dissolved In a low volatile solvent 21 by the application of heat and agitation to form a hot homogeneous varnish dispersicn 22.
• the dispersion is monitored 23 for viscosity and composition. If necessary, additional solvent 21 may. be added as shown at steps "B" on the flow diagram.
• NMP n-methyl pyrrolidone
• solvents such as dimethylformamid (DMF), meta cresol, cyclohexane, 1-formylplpridine, dimethyl acid amide, and other N-alkyl substituted amides are also suitable.
• a selected preform 25 is preconditioned 26 to remove excess moisture by heating at 250°F In a vacuum oven for 2 hours.
• the dried fabric 27 is then allowed to cool, it is weighed 28 and subsequently placed in tray 29 where
• the wet prepreg is placed in a cold-trapped vacuum oven 31 preheated to 125 ⁇ 0.5°C and vacuum baked at that temperature for 8 ⁇ 0.5 hours to form a dry prepreg 32. It Is then tested 33 for volatile content and rebaked if the volatile content exceeds 3% or r ⁇ saturated as necessary in accordance with step 0 of the flow diagram.
• Typical weight percentages of composite constituents, prepared with planar 3-D Type I (HMS) and Type II (VYB 70-1/2) preforms are presented in the following table.
• Thermld 600 15 135.0 116.0 131. 0
• the prepreg 32 is placed into a steel mold 33 (designed for a given part geometry), preheated to 250 ⁇ 5°C, and molded at 3.45 ⁇ 0.5 MPa in a similarly heated laboratory press.
• the pressure Is applied slowly to prevent excess resin flow out of the preimpregnated preform, yet fast enough to take the gel times of the resin into account for obtaining void-free, molded blanks.
• Final cure Is accomplished by leaving the preform In the heat press under load for 2 ⁇ 0.5 hours which provides a molded self-lubricative composite 35.
• the entire molding assembly Is allowed to cool below 100°C before removing the molded composite form.
• Another way of preparing the instant invention is to use specially designed steel molds, placed In a heated press, in conjunction with high thermal expansion silicone rubber cores or pressure Inserts.
• Still another way of preparing the instant Invention Is to utilize shape-retaining metal fixtures containing heating elements or such fixtures heatable by radio-frequency (RF) methods, placed In high pressure autoclaves for hot isostatlc pressing of the prepregs.
• RF radio-frequency
• Post cures may be acccomplished, if necessary, by subjecting the cured composite, in Its molded form, to the following post cure schedule. 1. Room Temperature to 232°C (450°?) in 2 hours and hold 2 hours
• Both the soft and the abrasive versions of the Type I and the inherently abrasive Type II fibers can be made non-abrasive, by the teachings of the instant Invention, when the reinforcement is exposed to intimate sliding contact with the mating (metallic) bearing surface by the normal wear process, at elevated temperatures;
• the highest load carrying capacity is provided by the inherently more abrasive Type II fibers, due to its lower modulus, greater flexibility and the resulting reduced breakage during molding and due to Its less brittle nature while under sliding at high loads, as compared to the more fragmentation prone Type I (graphitic) fibers.
• the mitigation of carbon fiber abrasiveness must be affected by the ability of the solid lubricant pigment to induce and propagate the rapid formation of a composite transfer film onto the mating metal surface. This film then protects the metal surface from the abrasive fibers and at the same time reduces carbon fiber wear;
• Thin film deposition techniques such as sputtering the additive mixtures on the mating metal and/or the polymeric composite surface, or enriching the surface by final soaking a new-dimensional composite part in a lubricative additive-rich varnish solution, lend themselves readily for this role;
• 3D orthogonal Type II (amorphous, abrasive carbon) fiber weave reinforced Thermid 600 composites can perform in an outstanding manner where the majority of the fiber lay is in the plane of sliding i.e., normal to the applied load. This degree of satisfactory performance depends a great deal on the selection of the additives described above, yet the highest compressive strength Is achieved automatically in that fiber lay configuration.
• the powdered Ga/In/WSe 2 compact and the reagent grade (NH 4 ) 2 HPO 4 was found to be an ideal solid lubricant additive/carbon-graphite fiber adjuvant combination.
• the Ga/In/WSe 2 compact does have both the thermal oxidatlve stability (up to 1000°F) and the film forming capacity leading to low friction and wear. It also shows great affinity to the Thermid 600 resin, resulting in excellent adhesion at the compact particle/resin interface.
• About 2 weight percent of (NH 4 ) 2 HPO 4 Is extremely effective in reducing both the friction and the wear rate of carbon-graphite fiber composites.
• the thermal degradative Achilles heel of a carbon-graphite fiber reinforced polymeric composite are the resin/fiber (primary) and resin/additive (secondary) interfaces. Superimposed is the inherently thermally unstable nature of certain low cost Type II fibers, where exposure to temperatures as low as 316°C (600°F) can cause crystallographic and/or oxidative changes that lead to composite deformation (i.e., thermal loss of bearing dimensions) even without any relative sliding movement and wear. Therefore, any Type II fiber used for the instant invention must be selected to be crystallographically and thermoxidatively as stable as the cost, application temperature, load, speed and required wear life allow it.
• the resin/fiber interface degration can be minimized by proper chemical/physical pretreatment of the carbon/graphite fibers for proper wetting by the resin and for the prevention of tribooxidative wear.
• the (NH 4 ) 2 HPO 4 graphite fiber adjuvant of the instant invention has a tendency of separating out at the fiber/resin interface, providing some protection at the most vulnerable site within the composite.
• Carbon/graphite tows should contain the smallest number of individual fiber strands commercially feasible for self-lubricating preform weaving, where each strand should be coated with a thin resin-varnish, containing very fine (possibly colloidal) forms of the Ga/In/Wse 2 compact powder, the (NH 4 ) 2 HO 4 adjuvant powder or any other advanced additive powder that satisfies the teachings of the Instant invention.
• the preforms woven from such pretreated tows, further Impregnated with the resin/additive varnish, will comprise the best prepregs for composite molding; and
• such composite may be reinforced by no more than 40 weight percent of a multidirectional, cylindrical weave of all or mostly Type I (graphitic, higher wear rates) fibers, containing higher volumes (e.g., 20 to 30 weight percent) of the transfer film formation enhancing solid lubricant additive (i.e., the powdered Ga/In/WSe 2 compact).
• Type I graphitic, higher wear rates
• solid lubricant additive i.e., the powdered Ga/In/WSe 2 compact.
• Type II weave reinforcements are required with a minimal amount of additives needed for the friction/wear level desired or tolerated for that application.
• Self-lubricating composites prepared in accordance with the teaching of this invention may be used as bushings and as bearing retainers in numerous applications where high load carrying capacities at high temperatures are required. These composites may also be used to fabricate gears, splines, liners of plain bearings and sliding pads for use In moving mechanical assemblies where self-lubrication, under extreme conditions, is required.

Landscapes

• Chemical & Material Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Engineering & Computer Science (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Organic Chemistry (AREA)
• Lubricants (AREA)
• Reinforced Plastic Materials (AREA)
• Computer And Data Communications (AREA)
• Data Exchanges In Wide-Area Networks (AREA)
• Small-Scale Networks (AREA)
• Manufacture Of Macromolecular Shaped Articles (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=22942625

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (30)

Citations (4)

Family Cites Families (2)

• 1981
  • 1981-03-30 US US06/249,243 patent/US4376710A/en not_active Expired - Fee Related
• 1982
  • 1982-03-22 DE DE8282901261T patent/DE3267511D1/de not_active Expired
  • 1982-03-22 JP JP57501315A patent/JPS58500444A/ja active Granted
  • 1982-03-22 EP EP82901261A patent/EP0075002B1/en not_active Expired
  • 1982-03-22 WO PCT/US1982/000346 patent/WO1982003406A1/en active IP Right Grant

Patent Citations (4)

Also Published As

Similar Documents

Legal Events